75
IRRIGATION AND DRAINAGE
IN JAPAN
(3rd Editi_on)
By
International Affairs Commission of The japanese
Society of Irrigation， Drainage and
Reclama tion Engineering
japanese Society of Irrigation， Drainage and
Reclamation Engineering
Tokyo， Japan， 1995
To Our Readers:
This book basically focuses on the spectrum of activities thatJSIDRE
members are involved in， and introduces the various “land improvement
projects" in which these capable engineers participate， both in Japan and
abroad. It also provides outlines of organizations that are closely related
to irrigation and drainage projects， together with their functions， and
background information， and is intended to provide quick and concise
answers to your questions on these subjects.
In the third edition， the obsolete data of the second edition， such as
statistics， and office addresses， etc.， is replaced with current
data. However， the statements and descriptions of the second edition are
kept as they were.
M.Okamoto
Contents
Chapter 1 Land Improvement Project Systems and JSIDRE . . . . . . . . .. 1
1・1Main characteristics of Japanese land improvement projects .... 1
1・2]apanese Society of Irrigation， Drainage and Reclamation
Engineering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .・・・・・・・・・・・・・・・・・ 2
1-2ol Establishment， organization and finance . ......... ........ .. 2
1 u2-2 Activities.・・・・・・・・@・・・・・・・・・・・・・・・・・・・・・・・・................. 3
Chapter 2 Background........................................... 0 • •• 6
2・1 Geography..................................................... 6
2・1・1Location and land area of Japan . . .. . .... . . . . . . . ... . . . . . ... .. 6
2-1-2 Temperature and precipitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 7
2-1・3Land improvement projects characterized by climatical
condi tions ................・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 8
2・1・4Population， and its density and regional distribution .. ..... .10
2・1-5National economy and agriculture ......................... .12
(1) GNP.................................・・・・・.................12
(2) Agricultural products .............. ... ... ...... ... .. ...... .12
(3) Foreign trade ............................................. .12
(4) Import of agricultural products and self-sufficiency rate . . . .13
2-1-6 Farmers and farming land ............ . . . . . . . . . . . . . . . . . . . . . .15
(1) Number of farmers and farming households .... . . . . . .... . . .15
(2) Agriculturalland. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
(3) Average agriculturalland holding size. . . . . . . . . . . . . . . . . . . . . .16
(4) Population， number of farming households and
agricul turalland by prefecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
(5) Irrigation rate. . . . . . . . . . . . . . . . . . ... . . . . . o' • • • • • • • • • • • • • • • • • • • .18
Chapter 3 Administration and Finance ............................. .19
3・1 National system .. .. . . . .. .. . . . ...... . . . . . .... . . . . . . .. . . . . . . . .. . .19
3・2 Ministry of Agriculture， Forestry and Fisheries and the
Agricultural Structure Improvement Bureau .................. .19
(1) Ministry of Agriculture， Forestry and Fisheries ..・・ー・......19
(2) Agricultural Structure Improvement Bureau .............. .20
(3) National Office and Regional Offices of the Ministry ...... .20
3・3 Related administrative organizations .......................... .21
(1) Prefecture. . . . . ，・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・..........21
(2) Sharing of projects with other ministries， agencies，
public corporations， etc. ................................... .21
(3) Public corporations ....................................... .22
3-4 Finance........................................................ 23
(1) Government.............................................. .23
(2) Land improvement project budget ......................... .23
(3) Investment on each menu of land improvement projects ... .23
Chapter 4 Land Improvement Projects............................. ..25
4-1 Land Improvement Law ....................................... .25
(1) Outline of Land Improvement Law . . . . . . . . . . . . . . . . . . . . . . . . .25
(2) Purposes and benefits of land improvement projects . . . . . . . .25
4咽2 Menu of land improvement projects............................ .26
4-3 Long-term plan ................................................ .26
4-4 How to proceed with a project ................................. .27
(1) Projects findings . ..... . . . .. . . .. . .. .. .. . . .... . .. . . . . .. ... . . .27
(2) Preliminary survey ........................................28
β) General implementation plan. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
(4) Apllication.. . . . ... ... .. ... . .. .. .. . . .. . .. .... . . . .. ... .. . .. . .29
4・5 Characteristics of the way to proceed with a project in japan .. .30
(1) Menu method ............................................. .30
(2) Main body of a project related to its scale. . . . . . . . . . . . . . . . . . .30
(3) Subsidies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
(4) Standardization of engineering ........................... ..31
(5) Method of judging the effects of projects. .・....•.•.•.•• .....32
Chapter 5 Related Organizaitions................................... .34
5・1Related academic societies ... . .. . . ... .. . .. . ... .. .. .. .... ....... .34
5・2 Organizations of engineers .................................... .35
5-3 Private companies ............................................. .35
5-4 Land Improvement District.................................... .35
(1) Origin.. . '" . . .. . .. ... . . . .. ... . . . . ... .... . .. . .. .. . . .. .... . .35
(2) Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
(3) Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
(4) Finance................................................... .37
5・5 Education and research.・・・・・・・・・ーー・・・・・・・・.. . . . . . . . . . . . . . . . . . . .37
(1) Type...................................................... .37
(2) Organization of courses .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
(3) Curriculum.............................................. ..41
(4) Employment...............................................41
(5) Graduate schools. . . . . . . . . . . . . . . . . . . . . . . . . . . . ; . . . . . . . . . . . . . .42
(6) Foreign students .... . ... .... . .. ...... . . ....... . . ....... ....42
(7) Junior colleges and h培hschools . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
(8) Special research institution attached to colleges ...... .. ....42
5・6 National Research Institute of Agricultural Engineering ... . ....44
5幽7 Other research and experiment institutes. . . . . . . . . . . . . . . . . . . . . . .44
Chapter 6 International Cooperation.. . . .. ... .... ..... .. . ........ ... .45
6-1 International academic societies . .. .. . . . . .. .. . .. .. .. .. .. . .. .. .. .45
(1) International Commission of Irrigation and Drainage
日CID)......................................................45
6・2 Official Development Assistance (ODA) ........................45
(A) JICA Oapan International Cooperation Agency) . . .. . . . . . . . . .46
(B) Overseas Economic Cooperation Fund (OECF) .............49
6・3]apanese embassies and international organizations ........... .50
6-4 Agricultural Development Consulting Association (ADCA) . . . . . .51
6-5 Tropical Agriculture Research Center ..........................51
6-6 Others......................................................... 51
Chapter 7 Paddy....................・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・..53
7-1 Varieties....................................................... 53
7・2 Increase against time in paddy fields and rice yield .............54
7・3 Reasons for increased yield . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
7-4 Agricultural inputs ............................................ .55
τ5 Food control system， demand for and supply of rice ............ .55
7・6 Excessive production， reduction of planting fields，
well-drained paddy field ....................................... .56
7嗣7 Mobilization of agriculturalland. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
Chapter 8 Miscellaneous............................................. 58
8-1 Agricultural machinery. . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . .58
8-2 Irrigation projects for non予addycrops. . . . . . . . . . . . . . . . . . . . . . . . . . 58
8・3 Earth works in reclamation projects . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
8-4 Projects of reclamation from sea or lake bottom................. 60
8-5 Disaster prevention projects ....................................62
8・6 Projects related to water and soil pollution. . . . . . . . . . . . . . . . . . . . . .62
8-7 Community sewerage systems and other infrastructures .......63
8・8 Concept of irrigation water requirement for paddy ..............63
8-9 Water management under a paddy irrigation system............ 64
(1) On-farm water management ...............................64
(2) On-plot water management ...............................‘65
8・10 Water rights: progress of urbanization and diversion of
water rights . . ...... ... . .. ... . . .. . .... ... . . ... . . .. . . . .. . . .. . ... . 65
8-11 Standard plot size and its development for paddy field land
consolidation projects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
8-12 Sophistication of irrigation and drainage facilities .............. 67
8-13 Drainage projects............................................... 67
Chα~pteγ1
Land Improvement
Project Systems and JSIDRE
1-1 Main characteristics of J apanese land improvement
projects
In]apan， the Agricultural Structural Bureau， Ministry of Agriculture，
Forestry and Fisheries is responsible for projects to cultivate virgin land，
develop agriculturalland， consolidate agriculturalland plots or construct
irrgation and drainage facilities， inc1uding reservoirs， barrages， pump
stations， canals， etc. for improving agricultural productivity. They are
now also active in constructing such infrastructures in rural areas as
community roads， domestic water supply systems， sewerage systems， etc.
Such projects are called “Tochi Kairyo Project Systems"，“Nogyo Kiban
Seibi Project Systems"， or “Nogyo Doboku Project Systems". In English，
theyare“Land Improvement Project Systems"，“AgriculturalInfrastruc.
ture Improvement Systems"， and “Agricultural Civil Engineering Project
Systems"， respectively. ]apan is richly endowed with high temperature
and rainfall， both of which are essential for growing paddy rice. As per.
acre yield of paddy rice is higher than any other field.grown crop，]apanese
land owners and farmers wished and still wish to have as large a paddy
field as possible to grow rice. It has， therefore， been the most important
task for ]apanese land improvement engineers to develop irrigated， not
rain-fed paddy fields.
To construct facilities necessary to develop irrigable paddy fields and
irrigate them， engineers with knowledge of civil engineering have con・
tinued to be irreplaceable.
-1-
Chaρter 1
At colleges and high schools， students who wish， after graduation， to
engage in such civil engineering-oriented works as mentioned above are
educated through a course different from common civil engineering.
These students are also taught subjects related to agriculture， in addition
to civil engineering subjects. Also， college teachers conduct studies and
research necessary for land improvement projects. Such studies and
research are also conducted at agricultural experimental stations of the
Ministry of Agriculture， Forestry and Fisheries.
Some of the students graduating from a land improvement course at
college will join the Ministry of Agriculture， Forestry and Fisheries， or a
prefectural organization to engage in land improvement projects. Injapan，
unlike some other countries， students graduating from a civil engineering
course at college， do not join， as a rule， the department responsible for
land improvement projects of the Ministry of Agriculture， Forestry and
Fisheries or prefectural offices to engage in land improvement projects.
Given these special circumstances， a group consisting of engineers (public
officials and employees of related private companies) who have knowledge
of civil engineering related to irrigation and who are engaged in land
improvement pr吋ectsfor the Ministry of Agriculture， Forestry and
Fisheries or prefecture， and college teachers， whose studies are directly or
indirectly related to such projects and who teach land improvement
engineering subjects， was formed.
Many of the above are the members of the japanese Society of
Irrigation， Drainage and Reclamation Engineering aSIDRE).
1・2 Japanese Society of Irrigation， Drainage and Reclamation
Engineering
1・2・1 Establishment， organization and finance
The japanese Society of Irrigation， Drainage and Reclamation Engi-
neering was established in 1929 and was approved as a corporated body in
ワ
Land lmprovement Project Systems and ]SIDRE
1970. The Society originated from the Japanese Society of Land Consoli圃
dation which was established in 1907， and still has headquarters in Tokyo.
There are six branch offices.
Its 1989 membership consisted of 12，393 regular members (educa-
tional institutions 583， government agencies 1607， prefectural agencies
6875 consultants and others 2721)， 228 student members and 379 support-
ing members.
The expenses of the Society are fully covered by membership fees
(1989 annual membership fee for a regular member: 7，200 yen)， funds
made available to the Society to conduct studies， and revenues from
publishing activities. Supporting members are private companies and
others who cooperate in the activities of the Society， and each pays a
membership fee of 70，000 ~ 130，000 yen a year.
A monthly journal is distributed at no cost to all members， and
members may participate in activities of the Society at a special discount
cost.
1-2-2 Activities
(1) Publishing of three journals
A monthly journal (in Japanese)， bimonthly reviews of research
papers (in either Japanese or English)， an English journal to be published
tWlce a year.
(2) Publication of books， materials and manuals on land improve-
ment engineering.
(3) National and branch conferences， lectures and workshops.
(4) Award honors for excellent research and projects.
(5) Conduct studies commissioned by the Ministry of Agriculture，
Forestry and Fisheries or other agencies.
(6) Academic exchange with foreign countries.
In addition to the above， the Society collects and keeps materials and
- 3 -
Chapter 1
books as reference sources for the members.
There are annual， national and branch conferences， where research
papers are given. At the national conference in 1988， about 262 papers
were presented， and a total of 267 papers were presented at branch
conferences. These papers cover broad areas， ranging from basic
research in land improvement engineering to applied studies directly
related to specific projects.
Table 1 Study groups in theJSIDRE
Study groups
Applied Hydraulics in Agricul-tural Engineering
Soil Physics
Irrigation for non-paddy crops
Materials & Construction
Rural Planning
Irrigation
Soil and Water Conservation
Applied Hydrology
Bioholonics
Rural and Farm Road
Members
174
208
450
500
509
1，590
340
173
68
135
Adress
Department of Rural Engineering， College of Agriculture， Ehime University， Tarumi， Matsuyama， 790
Department of Agricultural Engineering， Faculty of Agriculture， Iwate University， Ueda， Morioka， 020
Department of Agricultural Engineering， Faculty of Agriculture， Kyushu University， Hakozaki， Higashi-ku， Fukuoka， 812-81
Department of Regional Environmental Scienc泡， Faculty of Agriculture， Osaka Pre-fectural University， Sakai， Osaka， 591
Laboratory of Rural Planning， The National Institute of Agricu1tural Engineering， 2・1幽2，Kannondai， Tsukuba， Ibaraki， 305
c/o Prof. S. Sato， Tokyo University of Agri-culture， 1-1・1，Sakuragaoka， Setagaya-ku， Tokyo，156
Department of Environmenial Technology， Faculty of Agriculture， Kochi University， Monobe， Nankoku， 783
Department of Environmental Management Engineering， Faculty of Environmental Sdence and Technology， Okayama Univer-sity， Tsushirna-Naka， Okayama， 700
Arid Land Research Center， Tottori Univer-sity， Hamasaka 1390， Tottori， 680
]apanese Institute of Irrigation and Drain-age， NN bld_ 1-21-17， Toranomon， Minato-ku， Tokyo， 105
Land lmprovement Project Systems and ]SIDRE
Lectures and workshops， which are extension services of the Society
are held more than 20 times a year， a11 over the country.
The ]apanese Society of Irrigation， Drainage and Reclamation Engi-
neering covers a number of fields. In order to deepen studies and
research in individual fields， members and experts in a specific field come
together to form a study group to intensity and consolidate research and
feedback.
These study groups are shown in Table 1.
Chαpteγ2
Background
2・1 Geography
2・1・1 Location and land area of J apan
Location: ]apan is located in the temperate zone which is at the east
end of the Asia monsoon zone， and spreads from northeast to southwest.
It consists of the relatively large islands of Hokkaido， Honshu， Shikoku，
Kyushu and a large number of other smal1 islands.
Land area: Total and four main islands:
Total 378，000 km2
Hokkaido 83，500
Honshu 229，000
Shikoku 19，000
Kyushu 42，000
Land area by land c1assification:
Agriculturalland
Forest
Wilds
Water surface
Roads
Housing land*
Others
Total
5，470，000 ha
25.290.000
290，000
1，310，000
1，090，000
1，530，000
2，800，000
37，780，000
As shown above， ]apan is mostly covered with mountains， and is
richly endowed with forest. Housing land*， which is land for not only
Background
residences but also shops， offices and factories， accounts for only 4% and
factory land for only O.4gもofthe total housing land.
2・1・2 Temperature and precipitation
The last 30 (1951~1980) year average monthly temperature and
precipitation for seven cities (Sapporo， Sendai， Tokyo， Kanazawa，
Nagoya， Okayama and Fukuoka) where regional offices of the Ministry of
Agriculture， Forestry and Fisheries are located， are shown in Table 2 and
3.
U.S.S.R
lfアl
----ーーーー"ー--40'
ー一ー______35'
令_ OCρ
r'<';¥" マ1>-".
ー司幽ーヲー。F
ず
〆Figure 1 Japan.
- 7
(mm)
300
20日
Chapter 2
(mm)
30.C 400
20
10
。-10
1 2 3 4 5 6 7 8 9 10 11 12
① Sapporo
yearly mean temperature B.O'C annual precipitation 1， 15Bmm
(mm)
(mm)
。-10
1 2 3 4 5 6 7 8 9 1011 12
③ Tokyo
yearly mean 15.3"C annual 1，460mm
(mm)
400
(mm)
301: 400
10
。一10
1 2 3 4 5 6 7 8 9 1011 12
⑤ Okayama
yearly mean 14.6 "c annual 1，223mm
300
30.C
10
-10 1 2 3 4 5 6 7 8 9 1011 12
② Sendai
yearly mean 11.9"C annual 1，219mm
301:
20
|日
-10 1 2 3 4 5 6 7 8 9 1011 12
④ Kanazawa
yea rly mea n 14.0 "c annual 2，645mm
301:
20
10
-10 1 2 3 4 5 6 7 8 9 1011 12
⑥ Kumamoto
yearly mean 16.1 "c annual 1.9B9mm
Figure 2 Temperature and precipittation (rainfall and snow).
2-1・3 Land improvement projects characterized by climatical
conditions
The Japanese rainy season， called “Baiu" or“Tsuyu"， is generally
June and July， though somewhat differnt depending on the region. After
the rainy season， there also is heavy rain in most yeais when a typhoon
comes.
Fortunately， the hot summer Gune through August) and the rainy
一公一
Background
Table 2 Regional offices of the Ministry of Agriculture， Forestry and Fisheries
Office Adress
Hokkaido Development Bureau: Kita 8 Jyo， Nishi 2-1・1，Kita-ku， Sapporo，060
Tohoku Regional Agricultural Administration Office: 3-3-1， Hon Cho， Aoba-ku， Sendai，980
Kanto Regional Agricultural Administration Office: No_ 3 Godo Tyosha BLDG， 1・3・3， Otemachi， Chiyoda-ku， Tokyo，100
Hokuriku Regional Agricultural Administration Office: 2・2・60，Hirosaka， Kanazawa， 921
Tokai Regional Agricultural Administration Office: 1-2-2， Sanno Maru， Naka-ku， Nagoya，460
Kinki Regional Agricultural Administration Office: Shimochojya machi Sagaru， Nishitoin Dori， Kamikyo・ku，Kyoto，602
Chu-Shikoku Regional Agricultural Administration Office: 1-4-1， Shimoishii， Okayama， 700
Kyushu Regional Agricultural Administration Office: 1・2，Nino Maru， Kumamoto， 860
Okinawa General Office: 2-21-7， Maejima， Naha， 900
Table 3(1) Temperature (averagei 1961-1990) COC)
City Jan_ Feb_ Mar_ Apr. May Jun_ JuL Aug_ Sep_ Oct_ Nov_ Dec_ Mean
Sapporo 4_6 -4.0 -0_1 6.4 12_0 16.1 20.2 21.7 17.2 10.8 4.3 -1.4 8.2 Sendai 1.0 1.3 4.2 10.0 14.9 18.3 22.0 24_1 20.1 14.4 8.9 4.0 11.9 Tokyo 5.2 5.6 8.5 14.1 18.6 21.7 25.2 27.1 23.2 17.6 12.6 7.9 15.6 Kanazawa 2.9 2.9 6.0 12.1 17.0 20.8 25.2 26.6 22.1 16.1 10.8 6.0 14.1 Nagoya 3.7 4.3 7_6 13.8 18.4 22.0 25.8 27.1 23.1 17.0 11.5 6.2 15.1 Kyoto 4.0 4.5 7.6 13.9 18.7 22.4 26_5 27.7 23.4 17.1 11.5 6.5 15.3 Okayama 4.6 5.0 8.2 14.4 18.9 23.1 26.9 28.4 24.2 17.3 12.0 6.8 15.8 Kumamoto 4.9 6.1 9.6 15.4 19.5 22.9 26.9 27.6 24.0 18.1 12.3 7.0 16.2 Naha 16.0 16.3 18.1 21.1 23.8 26.2 28.3 28.1 27.2 24.5 21.4 18.0 22.4
Table 3(2) Precipitation (rainfall and snow) (average: 1961-1990) (mm)
City Jan. Feb. Mar. Apr_ May Jun. Jul. Aug. Sep. Oct_ Nov. Dec. Total
Sappor。 107 94 81 62 54 66 68 142 137 115 98 100 1129 Sendai 41 48 68 93 108 133 150 164 186 103 69 35 1204 Tokyo 45 60 99 125 138 185 126 147 179 164 89 45 1405 Kanazawa 293 195 156 147 150 207 250 171 247 202 265 305 2592 Nagoya 42 63 110 150 157 217 212 145 211 114 70 40 1534 Kyoto 50 65 110 151 153 247 234 142 202 112 69 39 1581 Okayama 30 59 95 93 137 213 134 73 185 75 40 18 1159 Kumamoto 59 78 121 159 202 392 392 189 157 89 73 49 1967 Naha 113 106 162 152 243 252 190 258 168 150 116 123 2036
-9-
Chapter 2
season come together. Thus， it is possible to grow paddy rice each
summer， once a year. In winter， however， temperatures are too low to
grow paddy rice.
judging from the figures of average rainfall， it may appear that there
is no need for japan to irrigate fields as it has suficient rainfall in the
summer/rainy season. It is not the case， however. From early times，
people in japan have been very active in irrigation. In some years， the
total rainfall does not reach the average and causes some deficit in
irrigation water requirement. In those cases， irrigation is required.
Also， even if rainfall is sufficient in terms of total monthly or irrigation
season rainfall， irrigation may be desired if a dry spell occurs during that
period and there is no rainfall when it is needed.
2・1・4 Population， and its density and regional distribution
The 1993 japanese total populatioin amounted to 125 million. Its
population density is 334 persons per square kilometer. In view of that，
japan is mostly covered with mountains and has a limited inhabitable land
area; this population density is said to be high in world;，comparison.
The population is not evenly distributed in japan， and is instead
concentrated in such big cities as Tokyo (11.8 million)， Osaka Prefecture
(8.7 mi11ion)， Aichi Prefecture， which has Nagoya (6.8 million)， and Kyoto
Prefecture (2.6 mi11ion)， and industrialized regions. In the coastal zone
extending from Metropolitan Tokyo to the northern part of Kyushu island，
about 70% of the population is concentrated.
Overpopulation in urban regions on one hand and underpopupulation
in rural areas on the other， resulting from the concentration of population，
is one of the most important problems in recent years which needs to be
solved. The total population of the cities with more than 100，000 people
was 65.0% in 1990.
The 1993 farmers' households are shown in Table 4.
- 10-
Backg:γound
Table 4 Farmers' households ( thousands)
Total Farmers' households(1993)
Prefecture households Part-time
(1990) Total Full-time
Class 1 Class 2
Hokkaido 2，015 79 37 30 12
Aomori 453 72 12 21 39 lwate 426 88 9 14 65 Miyagi 692 82 6 13 64 Akita 358 82 7 15 60 Yamagata 341 67 5 18 45 Fukushima 604 106 9 16 81
lbaraki 830 122 17 16 89 Tochigi 571 76 9 11 56 Gunma 600 62 12 13 37 Saitama 2，028 75 9 12 55 Chiba 1，797 96 15 18 64 Tokyo 4，694 12 2 10 Kanagawa 2，818 24 2 5 16
Niigata 705 114 7 15 92 Toyama 312 49 2 3 44 Ishikawa 359 37 3 2 32 Fukui 233 37 2 2 33 Yamanashi 262 32 7 8 17 Nagano 655 112 17 13 82 Gifu 601 65 4 3 57 Shizuoka 1，115 70 11 17 43 Aichi 2，161 79 10 10 60
Mie 545 60 5 3 52 Shiga 351 46 2 2 43 Kyoto 894 34 4 4 27 Osaka 3，040 19 2 2 15 Hyogo 1，775 93 10 6 77 Nara 411 25 3 3 19 Wak&yama 344 33 10 5 18
Tottori 179 34 4 5 25 Shimane 235 44 5 3 36 Okayama 608 76 11 5 60 Hiroshima 974 65 13 4 48 Yamaguchi 535 49 10 4 35
Tokushima 258 35 8 6 22 Kagawa 321 42 5 5 32 Ehime 511 56 13 9 34 Kochi 289 30 10 7 14
Fukuoka 1.624 79 15 10 54 Saga 250 40 6 8 26 Nagasaki 502 41 9 9 23 Kumamoto 575 76 22 19 35 Oita 409 53 12 7 34 Miyazaki 391 51 16 11 24 Kagoshima 657 83 31 13 39
Okinawa 363 28 10 4 14
Total 40，670 2，835 447 429 1，958
- 11-
Chatter 2
2-1・5 N ational economy and agriculture
(1) GNP
The 1992 GNP of ]apan presented by producers' price was
420，809 billion yen.
lndustrial distribution of GNP is as follows:
Agriculture， forestry and fisheries: 10，199 billion yen.
Manufacturing: 129，507
Construction: 46，959
Wholesale and retail: 59，272
Transportation and Communication:
Services:
Governmental services:
(2) Agricultural products
29，042
75，586
35，678
1992 agricultural products in]apan were as follows:
Total of all production: 11，215 bil1ion yen
Rice: 3，323
Vegetable 2，404
Hens and chickens 754
Rawmilk 797
(3) Foreign trade
(100%)
( 30%)
( 21%)
( 7%)
( 7%)
]apan is poor in natural resources， but is a highly industrialized
nation. The country imports enormous amounts of raw materials， pro-
cesses them into industrial products， and exports part of them. Thus，
]apan is actively engaged in foreign trade. ]apan also imports large
amounts of such food as wheat， feed， fish， etc.
The major export items of 1993 were， in the order of monetary
amounts， such transportation equipment as Passenger cars (5，250 billion
- 12-
Bα:CkgiγOU:官zd
yen) general rnachinery (9，226 billion yen)， electric rnachinery (7，560 bil1ion
yen)， Iron and Steel (1，613 billion yen). Total exports during the year
arnounted to 40，202 billion yen.
The major import iterns in industry sectors during the same year
were， also in the order of rnonetary arnounts: oil (3，139 billion yen)，
machinery (3，412 billion yen)， chemical industry products (1，942 bil1ion
yen)， textile products (1，833 billion yen)， natural gas (1，089 billion yen)，
metal rnaterials (778 billion yen) and textile materials (171 billion yen).
Total imports amounted to 26，826 bil1ion yen.
(4) Import of agricultural products and self-sufficiency rate
Rice is the only crop that Japan can self-sufficiently produce. It
imports other cereals， feed and others in large arnounts each year as repre-
sented by the 1993 figures below:
rnaterials X1，000 tons
wheat 5，814
maize(feed) 11，988
fruits and vegetables
coffee and cocoa 403
rneat 1，666
raw cotton 528
wool 133
fish and shellfish 2，711
tirnber
X1，000 rnillion yen
126.7
167.1
568
82.9
757.6
76.2
55.0
1，551.3
1，130.8
Imported food， fish and tirnber shares about 28% of total irnport on a
monetary basis
As a result of irnports of large amounts of agricultural products， its
self-sufficiency rate (the proportion of dornestic production to cover dornes司
tic consumption) has declined to 12% for wheat， and 4% for soybean in
一13ー
(CZ¥CO#)弘℃℃偲仏
5.0
4.5
4.0
(2¥COH)ωυ一』己主O』回
Surplus
C 0 ..... C
~ 20 E 、__，〉、てコて3ro Q..
3.5
15
10
(COMCO一一一一
E)8℃C〉
PO」白
1985 1975 1980 1965 1970 L
Year
Cultivated land. qο ρL
VA u
σ0 ・・E且E
i
(%)
140
Japan UK 40
20
Trend of Self.sufficiency ratio in calorie-supply base (Source: Food consumption statistics， OECD)
1 A
90 (Yea.r)
85 ハ |
~1970 75 80
Figure 4
Background
1992.
]apan has become the biggest country in the imports of agricultural
products and its calorie self-sufficiency has declined from 79% in 1960 to
46% in 1990.
These figures are small even compared with other industrialized
countries as shown below， and the government hopes to improve it. In
1993， the calorie basis self-sufficiency (%) in industrialized countries were:
U.S.A. 113， France 143， West Germany 94， United Kingdom 73，
]apan 37.
2.1・6 Farmers and farming land
(1) Number of farmers and farming households
Statistics for the number of farmers and farming households for 1965，
after the country was more or less stabilized after the disorder of the
Second World War， and that for 1993 are compared below:
Total Farmers' Total Farming
population family (%) households households %
(X1，000) (X1，000) (X1，000) (X 1 ，000)
1965 98.275 30，083 30.6 24，082 5，665 23.5
1993 124.764 13，107 10.5 43，077 2，834 6.6
As shown above， farmers and farming households have dramatically
decreased in this country， as in other industrialized countries.
These farmers and farming households may be classified into full-
time farming households and part-time farming households from the
standpoint of degree of dependency on farming.
Here， full-time farmers refer to those farmers fully engaged in farm-
ing， Class 1 part-time famers to those farmers who have some other job in
- 15-
Chapter 2
addition to farming and who earn more money from farming， and Class 2
part-time farmers to those farmers who have some other job in addition to
farming and who earn more from that job.
Total Full-time Part-time (Class 1) (Class 2)
farming farming farming
households households households
(X1，OOO) (Xl，OOO) (X1，OOO) (X1，OOO) (X1，OOO)
1960 6，057 2，078 3，979 2，036 1，942
1993 4.403 447 2，388 429 1，959
As shown above， most of today's farmers are part-time farmers， and
moreover are Class 2 part-time farmers who earn more money from work
other than farming.
(2) Agriculturalland
According to the c1assification made by the Ministry of Agriculture，
Forestry and Fisheries， agriculturalland area by type is as below:
Paddy field 2，781 (X1，000 ha) (1993)
The other field 2，342
Ordinary field 1，243
Orchard land 439
Pasture 661
Total 5，125
(3) Average agriculturalland holding size
Exc1uding Hokkaido， the average Japanese farming household holds
farm land of about 1 hectare. Generally， the farm size gets smaller as you
move from the northeast region to the southwest region。
- 16-
Backg:γ'Ound
Table 5 Agriculturalland (1993)
Total Agriculturalland (ha)
Prefecture geographical Non-paddy (k ヮ2) Total Paddy
total ordinary orchard pasture area lKm
Hokkaido 83，520 1，206，000 240，600 965，350 422，900 3，950 538，500
Aomori 9，247 168.100 90，500 77，600 32，500 26，900 18，200 lwate 15，277 171，600 101.000 70，580 31，500 6，880 32，200 Miyagi 7，292 147，600 118，000 29，660 19，000 3，310 7，350 Akita 11，435 158，900 134，800 24，110 13，800 4，220 6，090 Yamagata 9，327 135，000 104，800 30，220 12，700 13，300 4，220 Fukushima 13，784 176，400 114，800 61，600 36，500 18，400 6.700
lbaraki 6，094 193，000 109，200 83，770 72，000 10，600 1，170 Tochigi 6，414 138，500 107，900 30，690 23，300 4，410 2，980 Gunma 6，356 90，600 33，400 57，230 40，300 14，600 2，330 Saitama 3，799 94，300 55，700 38，568 30，500 7，910 158 Chiba 5，150 145，200 85，900 59，348 53，900 4，500 948 Tokyo 2，164 10，500 577 9，896 7，650 2，040 206 Kanagawa 2，402 25，500 5，390 20，182 14，700 5，410 72
Niigata 12，112 189，900 167，300 22，580 17，400 3，600 1，580 Toyama 4，252 65，800 63，100 2，739 1.690 763 286 lshikawa 4，197 49，900 41，600 8，298 5，400 1，960 938 Fukui 4，192 45，300 41，200 4，071 2，990 774 307 Yamanashi 4，254 30，500 10，100 20，450 4，520 14，800 1，130 Nagano 13，133 131，000 67，500 63，530 36，900 22，000 4，630 Gifu 10，596 65，700 49，700 15，940 8，550 5，900 1，490 Shizuoka 7，235 85，800 29，300 56，380 18，000 36，600 1，780 Aichi 5，138 89，400 52，600 36，690 29，200 6，880 610
Mie 5，778 70，400 53，900 16，446 8，540 7，790 116 Shiga 4，016 58，900 54，000 4，923 3，310 1，500 113 Kyoto 4，613 35，600 28，200 7，391 3，740 3.580 71 Osaka 1，869 17，500 12，600 4，905 1，220 3，680 5 Hyogo 8，381 86，900 78，400 8，509 5，340 2，630 539 Nara 3，692 26，600 19，100 7，490 2，910 4，560 20 Wakayama 4，725 40，100 13，900 26，153 2.590 23，500 63
Tottori 3，494 40，700 26，700 14，000 8，660 4，200 1，140 Shimane 6.628 46，500 36，100 10，325 6，610 2，760 955 Okayama 7，091 83，100 63，500 19，620 13，000 5，120 1，500 Hiroshima 8，467 71，700 51，100 20，630 9.870 9，200 1，560 Yamaguchi 6，106 59，700 47，800 11，907 5，420 5，920 567
Tokushima 4，145 37，300 22，900 14，450 6，400 7，770 280 Kagawa 1，882 38，400 29，900 8，428 2，860 5.520 48 Ehime 5，672 69，700 28，700 40，996 6，780 34.000 216 Kochi 7，107 35，100 26，200 8，823 3，740 4，830 253
Fukuoka 4，963 102，700 78，100 24，523 9.210 14，900 413 Saga 2，440 64，400 47，100 17，274 5，620 11，540 114 Nagasaki 4，112 59，800 27，100 32，685 22，100 10，400 185 Kumamoto 7.216 136，100 79，000 57，080 26，800 22，700 7，580 Oita 6，338 69，400 46，100 23，350 11，000 9，320 3，030 Miyazaki 7，198 74，700 40，000 34，720 27，100 6，290 1，330 Kagoshima 9，167 138，000 45，100 92，850 75，200 14，900 2，750
Okinawa 2，255 46，700 944 45，730 38，900 2，740 4，090
Total 377，835 5，124，500 2，781，411 2，342，690 1，242，820 439，057 660，813
- 17-
Chapter 2
(4) Population， number of farming households， and agriculturalland
by prefecture
As stated above， the average farm size is about only 1 hectare injapan，
owing to a thorough agricultural land reform which was implemented
during the occupation of japan after the Second World War.
Under the Agricultural Land Reform， carried out from 1945 to 1947，
any farmer was prohibited to own mQre than 5 hectares in Hokkaido and 3
hectares in other regions， to break up the land-owner system. Any
farming land exceeding the limit was purchased by the government， and
sold at low prices to tenant peasants who had been actual1y cultivating it.
The subsequent drastic inflation meant that the tenant peasants
acquired the land almost at no cost. In this way， al1 thejapanese farmers
became land-owner farmers of smal1 farm size after the Second World
War.
During the pre-war period of the land-owner system， no land improve-
ment project was implemented as it was meant to be for the interest of
land owners. In other words， no attention was paid to improve the labor
productivity of tenant peasants， and only projects to improve land produc-
tivity were carried out to increase the income of land owners from farm
rent.
As a result of the Agricultural Land Reform， however， it has become
possible to implement land improvement projects to improve labor produc-
tivity as wel1 as land productivity， since al1 farmers have become land
holding farmers.
(5) Irrigation rate
Paddy fields are almost 100% irrigated. There are few rain-fed paddy
fields in japan. Contrarily， the irrigation rate for non-paddy fields has
just exceeded 10%， only recently.
- 18-
Chαpteγ3
Administration and Finance
3-1 National system
]apanese government follows the three power system of legislation，
administration and judicature， each of which is independent from the
other.
The judiciary branch consists of the Supreme Court， high courts，
district courts， family courts and summary courts.
The legislative powers are vested in the Diet which is the sole law-
making body and consists of the House of Representatives and the House
of Councilors. Both representatives and councilors are elected by the
people.
Administrative powers are vested in the hand of the Cabinet， which
has eleven ministers: (1) ]ustice， (2) Foreign Affairs， (3) Finance， (4)
Education， Science and Culture， (5) Health and Welfare， (6) Agriculture，
Forestry and Fisheries， (7) International Trade and Industry， (8) Trans-
port， (9) Posts and Telecommuniations， (10) Labor， (11) Construction， aild
the Agency for Home Affairs.
]apan is divided into 47 prefectures and further into about 3，000 cities，
towns and villages.
Each prefecture， city， town and village has its own assembly and
head. Both head and assembly members are elected by the residents.
3-2 Ministry of Agriculture， Forestry and Fisheries and the
Agricultural Structure Improvement Bureau
(1) Ministry of Agriculture， Forestry and Fisheries
- 19-
Chapter 3
The Ministry of Agriculture， Forestry and Fisheries consists of five
bureaus， three agencies and numerous sections， as listed in Table 6.
Land improvement projects are administered and managed by the
Agricultural Structure Improvemen t Bureau.
Table 6 Organizational Structure of the Ministry of Agriculture， Forestry and Fisheries
Ministry of Agriculture， Forestry and Fisheries Minister's Secretariat Economic Affairs Bureau Agricultural Structure Improvement Bureau Agricultural Production Bureau Livestock Industry Bureau Food and Marketing Bureau FoodAgency Forest Agency Fisheries Agency
(2) Agricultural Structure Improvement Bureau
The Agricultural Structure Improvement Bureau is organized as
shown in Table 7. Titles of individual departments and sections are also
described there.
Table 7 Organizational Structure of the Agricultural Structure Improvement Bureau
Agricultural Structure Improvement Bureau Agriculture Administraition Department Planning Department
Planning and Coordination Office ム町
l 恥阿均附M叫♂伊抑向gional叩側刷na凶a叫lP… 討
Rural Development Policy Planning Office Resources Division Project Planning Division
Construction Department Design Division Construction Planning and Coordination Office Overseas Cooperation
Irrigation & Drainage Division Land Improvement & Consolidation Division Land Improvement & Consolidation Project Promotion Office
Land Development Division Disaster Prevention Division
(3) National Office and Regional Offices of the Ministry
There are 6 offices of the Ministry of Agriculture， Forestry and
- 20ー
Administration and Finance
Fisheries for the efficient administration of the policies of the Ministry in
respective regions. Each regional office has departments and sections
roughly similar to those of the Ministry located at Kasumigaseki in Tokyo，
to carry out respective works in each region.
The Hokkaido region has no regional office of the Ministry， but has a
integrated organization similar to the national government to administer
affairs of not only the Ministery of Agriculture， Forestry and Fisheries，
but also such other ministries as the Ministry of Construction. Within it，
there are deparatments and sections to carry out works assigned to the
Agricultural Structure Improvement Bureau.
Within the region covered by each regional office， there are ten to
thirty five national offices (total133) to conduct government-operated land
improvemenat projects. Such national offices are closed when the con-
struction project is completed.
3・3 Related administrative organizations
(1) Prefecture
Each prefecture also has departments and sections in charge of land
improvement projects. Generally， there are two to three depar-tments in
charge of land im provemen t proj ects in a prefectur al office. Land im prove-
ment engineers implement land improvement projects in their prefectural
area， with the advice and guidance of the Agricultural Structure Improve-
ment Bureau and related departments and sections Of the respective
regional office of the Ministry of Agriculture， Forestry and Fisheries.
Prefectures with peculiar agricultural products have special depart-
ments such as Department of Apples， Department of Oranges， etc.
(2) Sharing of projects with other ministries， agencies， public corpo・
ratIons， etc.
Land improvement projects are one type of public services. To be
more specific， it is one of the civil engineering services. What organiz~tion
- 21-
Chapter 3
of government carries out what public service depends on individual
countries. In ]apan， public services are shared， for example， f100d control
and highway projects are executed by the Ministry of Construction，
harbor projects by the Ministry of Transport， municipal water supply
projects are conducted by cities under the supervision of the Ministry of
Health and Welfare.
(3) Public corporations
Public corporations are extra-government organizations. In addition
to those mentioned below， there are a number of public corporations，
including the ]apan Highway Public Corporation， to perform public servi-
ces. Of those public corporations， a large number of land improvemnet
engineers work for the following two public corporations:
1. Agricultural Land Development Public Corporation
The Corporation cultivates forests and wildernesses to develop new
agriculturalland. It has its headquarters in Tokyo， and about 3 branch
offices and 20 project offices are distributed all over the country. The
Corporation has 586 employees， and its projects amounted to 32.8 billion
yen in 1987. In terms of reclaimed land， it reclaimed 2，100 ha of pasture
land each year. Since 1982， it has been qualified to carry out services
abroad， too.
2. Water Resouces Development Public Corporation
The Corporation is responsible for construction， operation and main-
tenanace of reservoirs， barrages and canals On the six major river basins，
specially designated by law. As the services provided by the Corporation
are comprehensive， the land improvement engineers on leave from the
Ministry of Agriculture， Forestry and Fisheries and the civil engineers on
leave from the Ministry of Construction are working together. There are
also engineers directly employed by the Corporation. It has its headquar-
ters in Tokyo， 4 regional branch offices and 54 offices for operation/
maintenance and construction of water resources facilities. It has about
- 22-
Administration and Finance
2，000 employees， of which 60% are engineers， and its annual construction
services amounted to 149.2 billion yen in 1988， and operataion/mainte-
nance services to 15.7 billion yen， on the average from 1980 through 1986.
3-4 Finance
(1) Government
The government budget of 1994 was as below:
total: 40，854.8 billion yen
Ministry of Agriculture， Forestry and Fisheries 3，418.8 bil1ion yen
Agricultural infrastructure development 1，168.3 billion yen
references:
River projects: 1，193.5 billion yen
Sewerage projects: 1，050.4 billion yen
Road projects: 2，494.7 bil1ion yen
Harbor projects: 353.2 billion yen
(2) Land improvement project budget
The Agricultural Structure Improvement Bureau spent 1，168.3 bi1lion
yen on various land improvement pr句ects，and the contents of projects by
type wi11 be described later. As mentioned above， the portion of the
budget that the Agricultural Structure Improvement Bureau spent on land
improvement projects accounts for 34% of the total budget of the Ministry
of Agriculture， Forestry and Fisheries and 139もofthe total budget of all
public survices.
(3) Investment on each menu for land improvement projects
The costs of land improvement projects are paid from subsidies by
the national government and prefectures， and by direct payment of
farmers， who are the beneficiaries.
The total investment in projects in 1994， including not only funds
- 23ー
Cha争teγ3
provided by the government and prefectures but also those paid by farmers
is as below:
total: 2，024.4 billion yen
irrigation and drainage projects: 394.0 billion yen
land consolidation projects: 250.2 billion yen
farm and rural roads projects: 286.5 billion yen
non-paddy agriculturalland development projects: 104.7 billion yen
rural infrastructure development projects: 423.3 billion yen
- 24-
Chα~pteγ4
Land Improvement Projects
4・1 Land Improvement Law
(1) Outline of Land Improvement Law
In Japan， land improvernent projects are carried out under a law called
the Land Irnprovernent Law. This law Was initially enacted and enforced
in 1949 to cornbine and irnprove two pre-war laws: the Land Consolidation
Law and the Irrigation Association Law:， and has gone through several
revisions in response to social changes.
This law states the objectives and goals of land irnprovernent projects，
the way to irnplernent projects， and the organization and rnanagernent of
Land Irnprovernent Districts (farrners associations to operate and rnaintain
facilities which are to be forrned upon cornpletion of construction works).
(2) Purposes and benefits of land irnprovernent projects
As for the purposes of land irnprovernent projects， the Land Irnprove-
ment Law states，“land improvement projects airn through the develop-
ment of agricultural infrastructures (agriculturalland and accornpanying
social infrastructures)， to (1) increase land and labor productivity， (2)
increase total agricultural production， and (3) irnprove the agricultural
structure by rneans of diversification" .
In the article for the Long-Terrn Plan for land irnprovement projects in
the Land Improvernent Law to be described later an expansion of farm size
(or agriculture business scale) is added to the three iterns rnentioned above
for the irnprovement of agricultural structure. As a result of these
projects， it is expected that the irnprovernent of agricultural structure will
- 25-
Chapter 4
be realized， the country will be richer， vi1lage economies will be revitalized
and the natural environment will be better preserved.
4・2 Menu of land improvement projects
The Agricultural Structure Improvement Bureau provides various
projects as land improvement projects. Today， projects cover a wider
variety than imagined from the word “land improvement project". When
the law was enacted， projects coverd only reclamation， irrigation， drainage
and land consolidation， which were thought to directly contribute to the
expansion of agriculturalland and to the improvement of both land and
labor productivity and safety to natural disaster. Subsequently with
change in social conditions， projects were requested to cover development
of infrastructures for daily life of people living in farm vil1ages， including
local roads， ditches， sewage， parks， meeting houses， etc， in addition to the
development of facilities for agriculture.
Today， the Bureau provides the following projects:
1 irrigation and drainage
2 agriculturalland consolidation
3 farm and rural roads
4 comprehensive development of non-paddy agriculturalland
5 comprehensive development of rural areas
6 disaster protection
7 reclamation of agriculturalland
8 reclamation from sea or lake bottom
4・3 Long -term plan
The Ministry of Agriculture， Forestry and Fisheries enforced the
Fundamentals of Agriculture Law in 1961. The law aims to promote
diversification and expansion of farm size or the scale of an agricultural
operation in it. In accordance with the Law， the “Prospect of Long-Term
- 26-
Land lmprovement Projects
Demand for and Supply of Agricultural Products" was prepared. The
government policies related to land improvement projects have been made
along the line of this Prospect.
As land improvement projects need a considerable amount of funds
and a long pregnant period for the completion of planning， design and
construction， the government must make decisions on the priority of
individualland improvement projects on the basis of long-term prospects
of agriculture.
In response to the long-term prospect of supply and demand as
mentioned above， the Land Improvement Law was revised in 1964， and
long-term plans started to be made for land improvement projects. These
long-term plans are made by the Ministry of Agriculture， Forestry and
Fisheries， to be approved by the Cabinet.
These long term plans describe the goals of the land improvement
projects， the area of agriculturalland to be covered by the projects on the
basis of the long-term plan， the necessary amount of investment for
individual land improvement projects within a certain period as es回b-
lished in the long term plan. The long-term plan which established the
goals of projects during the specific ten years started in 1965. Today， it is
in the third phase. The total investment is 30，400 bil1ion yen， and the
proportion of achievement to the goal in 1988 was 35% (10，637.2 billion
yen).
4-4 How to proceed with a project
In ]apan， the Land Improvement Law provides the way to proceed
with a land improvement project.
(1) Project findings
For project findings about land improvement project， survey offices
specified for land improvement projects findings and establishsed in each
- 27ー
Chapter 4
district by the Agicultural Structure Improvement Bureau conduct， on a
continuous basis. All the costs and expenses for this survey are paid by
the national government. Prefectures also cooperate in these project
findings. The engineers of survey offices study the desires and condi-
tions of cities， towns and villages in a potential project area and discuss
these with the Land Improvement District. In this way， they find a
candidate district for a project. In Japan， as most irrigated land is
managed by the existing Land Improvement Districts， it will be almost
unnecessary to newly establish a Land Improvement District for future
laIid imprvement projects (an irrigation project in this il1ustration). The
details of organization and functions of a Land Improvement District will
be described in a later section.
(2) Preliminary survey
At this stage， after a survey is finished， a Land Improvement District
designates a district for which a project is expected to be carried out， and
requests the Agricultural Structure Improvement Bureau to make a direct
survey on the district， on the assumption that the project wil1 be imple-
mented. This survey Is cal1ed “District Survey".
It takes three to five years to finish the survey. All costs and
εxpenses are paid by the government. The survey consists of“Basic
Survey" to obtain data on the natural， social and economic background of
the district surveyed， and data necessary to design irrigation facilities， and
“Benefit Survey" to study the effects of the project. On the basis of such
data， the engineering feasibility of the project is examined， a “rough plan"
is made， and project costs are estimated. While the survey is progressing，
the Land Improvement District repeats lobbying to the government so that
the project will be actual1y implemented and realized. In lobbying， that
more than 90% of the farmers whowill be the beneficiaries of the project
possibly agree to pay part of the expected project costs is a prerequisite.
- 28-
Land lmprovement Projecお
(3) General implementation plan
When the Agricultural Structure Improvement Bureau judges， on the
basis of the “District Survey"， that the project will be feasible， it makes
more precise estimates of project costs and structural designing. It takes
about two to three years. This work is called "General Implementation
Design". The costs will be paid by the farmers upon completion of the
projects. A considerable part of costs is paid from subsidies from the
government and the prefecture， however.
The land improvement engineers of the Agricultural Structure
Improvement Bureau and the prefecture present information on a basis of
the achievements of the work so far carried out， to the farmers and the
Land Improvement District. If the Land Improvement District and the
farmers give an informal consent to the proposed project after presenta-
tion， the project will move to next stage.
(4) Application
The budget of theJapanese government is prepared on a yearly basis，
and is approved by the Diet. It is therfore essential that more than ninety
percent (though two thirds under the law) of farmers expected to be the
beneficiaries of the project agree to implementation of the project (that
means that the farmers will pay part of the project costs)， immediatly after
the budget requested by the Agricultural Structure Improvement Bureau
is included in the budget prepared by the Ministry of Finance and is
approved by the Diet. Upon satisfaction of this prerequisite， the Land
Improvement District officially presents to the government an“Applica-
tion for Implementation of Project" based on the Land Improvement Law.
At this stage， the Agricultural Structure Improvement Bureau opens
an office for the project.
The government again makes the decision whether to implement this
project or not. The government asks professors and experienced engi-
- 29-
Chapter 4
neers their views on the project， and makes the decision.
Then， the plan of project is public1y announced to let those interested
review the project documents. Any objections are properly handled.
Finally， the project plan is confirmed， and the local office of the Agricultu-
ral Structure Improvement Bureau begins construction work.
The above is the case of a irrigation project operated by the national
government. However， most part of the above discussion almost applies
also to those projects by prefectures.
4-5 Characteristics of the way to proceed with a project in
Japan
Below， the way the Agricultural Structure Improvement Bureau
proceeds with a land improvement project is compared with other coun-
tries methods.
(1) Menu method
Various menus are provided in term of contents and benefits of
facilities to be constructed by a project， and an organization such as the
Land Improvement District may select what they need to meet their
requirements from the menus.
(2) Main body of a project related to its scale
The main body to implement a land improvement project is either the
national government (Ministry of Agriculture， Forestry and Fisheries)， a
pref，配tureor a Land Improvement District， though there are some exceptions.
Except for reconstruction from disasters， responsibility for a project is
determined by the scale of that project. The scale is defined not by
project costs but by the acreage of agricultural land which will receive
benefit from this project. For example， an irrigation and drainage project
will be implemented by the Ministry of Agriculture， Forestry and Fisher-
- 30-
Land 1 mprovement Projects
ies， if the beneficiaray paddy acreage is more than 3，000 ha of paddy， or by
the Land Improvement District if it is less than 200 ha of paddy. Such
criterium figures for beneficiary agriculturalland area differ depending on
the type of project. For instance， a rec1amation project wil1 be a govern-
ment operated project if the beneficiary agriculturalland acreage is larger
than 400 ha.
As will be mentioned below， the proportion of subsidy by the govern-
ment or a prefecture differs depending on the type of project and the scale
of a project， that is， who implements the project.
(3) Subsidies
The costs of land improvement projects are， as a rule， paid by the
beneficiaries. Part of the costs is paid by the farmers， who are the direct
beneficiaries. To be more specific， the costs remaining after the subsidies
from the government and the prefecture will be paid by the farmers with a
long term low interest loan. Generally， the loan had an annual interest of
3.5 to 5.5%， and was paid back in 15 years with 2 years of deferment after
completion of construction works in case of government operated irriga-
tion and drainage projects.
Operation and maintenance of completed facilities wil1 be commissi-
oned to a Land Improvement District in almost all cases. No operation
and maintenance costs are subsidized by the government or the prefecture，
and the farmers (members of the Land Improvement District) have to pay
them. In order to reduce the burden of operation and maintenance costs
of the farmers， a service was started in 1975 by which the government
gives subsidies to cover part of those costs only in special cases， but the
total subsidies amount only to 1，600 million yen a year.
(4) Standardization of engineering
As land improvement projects are public projects to be implemented
- 31-
Chapter 4
with tax revenues， facilities to be constructed by projects of the same type
have to be standardized throughout the country. Therefore， the Agricul-
tural Structure Improvement Bureau has prepared manuals to be followed
when planning projects and designing facilities so that there wiU be no
discrepancies in the level， capacity and density of facilities to be con-
structed through land improvement projects to be independently imple-
mented in various parts of the country. These manuals are called “Plan-
ning and Design Standards" and have been published by the ]apanese
Society of Irrigation， Drainage and Reclamation Engineering.
This system of adopting such standardized engineering has other
advantages. Standardization eliminates differences among the engineers
in charge. Moreover， any engineer can get the results if he has a certain
degree of background. On the other hand， such standardization has the
disadvantage of making it difficult to take advantage of experience in
planning and designing. In japan， experienced executive engineers par-
ticipate in planning and design， taking into consideration newly developed
technology and social and natural charateristics of the region where the
project is to be implemented， in order to cover this demerit. Also， as the
manuals adopt as criteria only those technologies whose safety and econ田
omy have been guaranteed， there will be no need of apprehension that
structures of poor quality may be constructed， as far as design and
construction works are reviewed with reference to the manuals.
(5) Method of judging the effects of projects
Since the Second World War， the Agricultural Structure Improvement
Bureau has been using “Cost Benefit Ratio" (BC Ratio) as the criterium to
judge the economical feasibility of land improvement projects. Thus，
Internal Rate of Return (IRR) method is not used.
In calculating the BC Ratio， the problem is what items should be
included in the calculation. The current method of the Agricultural
- 32-
Land lmprovement Projects
Structure Improvement Bureau includes only those benefits which are
direct results of the project， but does not include those benefits of indirect
and secondary results. For instance， as benefits resulting from an irriga.
tion and drainage project for paddy field， water shortage at the time of dry
spell will be eliminated and reduction in rice production caused by water
shortage wil1 be eliminated since reservoirs， barrages and canals will be
constructed. With the improvement of drainage of water.stagnant paddy
fields by construction of draining facilities， wheat or barley may be grown
as a second crop in winter seasons， whereas it was not possible to do so on
damp paddy fields. Later， as project costs increased， these two benefits
became insufficient by themselves to justify a project， i.e. to get a figure of
BC Ratio larger than one， in some cases. Then， benefits of reducing work
hours necessary for water management resulting from construction of
irrigation facilities was included in the calculation. Effects of irrigation
and drainage projects， such as stabilization of prices of agricultural pro-
ducts， secondary effects of construction investment on regional economy，
improvement of hygienic conditions， suppression of flood runoff， or grad.
ual infiltration of groundwater resulting from irrigation are not covered in
these calculations yet.
- 33-
Chαpteγ5
Related Organizations
5-1 Related academic societies
Many of the members of the ]apanese Society of Irrigation， Drainage
and Reclamation Engineeing are carrying out research in their respective
fields， as well as being members of other academic societies. Major
societies are listed below， and information about them is given in the Table
8.
Table 8 Related academic societies
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The Society of Agricultural Machinery，]apan
The Society of Agricultural Structures， ]apan
The Society of the Science of Soil and Manure，]apan
Research Association of Soil Physics， ]apan
The ]apanese Society of Rural Planning
Members Adress
702 Division of Environmental Science and Landscape Architecture， Faculty of Horti. culture， Chiba University， Matsudo， Matsudo・City，271
1，489 BRAlN， 1.40.2， Nisshin cho， Omiya， 331，
503 c/o National Food Research Institute， Tsukuba，lbaraki
2，096 6・26.10・202，Hongo， Bunkyo.ku， Tokyo
743 NODAI Research Institute， Tokyo Univer. sity of Agriculture， Sakuragaoka， Setagaya， Tokyo，156
890 5.16開9，Honkornagome， Bunkyo-ku， Tokyo， 113
]apan Society of Civil Engineers 26，212
The ]apanese Society of Soil 13，180 Mechanics and Foundation Engineering
Yotsuya 1， Shinjuku.ku， Tokyo
2-23， Kanda-awaji-cho， Chiyoda.ku， Tokyo
- 34-
Related Organizations
5・2 Organizations of engineers
Members of the ]apanese Society of Irrigation， Drainage and Recla-
mation Engineeing are active in planning， surveying， designing， and
construction of land improvement projects， not only as researchers and
teachers， but also as public officials in the government and prefectures，
and employees of construction and consulting companies. Also， organiza-
tions for special objectives have been established.
5・3 Private companies
Private companies engaged in land improvement projects may be
roughly classified into two groups. They are consulting and construction
compames.
Consulting companies get orders from the government to conduct
surveys， make plans， and to design facilities necessary for the implementa-
tion of that project.
Construction companies carry out actual construction work in accor-
dance with the design thus prepared. In ]apan， it is not the custom to
employ some other consultants to supervise construction work. Engi-
neers of the government or prefecture supervise the work.
5-4 Land Improvement District
(1) Origin
Under the Land Improvement Law， in order to apply for a land
improvement project or in order to operate and maintain facilities con-
structed through a project， farmers must organize a farmers' organization
called “Land Improvement District". In many cases， however， there are
already irrigation associations of farmers which were estabished more
than some hundred years ago， and these associations have been active as
water users' organizations prior to the Second World War.
Another predecessor of the “Land Improvement District" is the “Land
- 35ー
Chapter 5
Consolidation Association"， which was an organiozation of land owners
for agriculturalland consolidation projects.
Of course， in those areas where a project is to be implemented and
where there were no agriculturalland or irrigation facilities prior to the
implementation of the land improvement project (such as a reclamation or
irrigation project to be implemented to construct completely new irrigation
facilities) a“Land Improvement District" has to be established when
applying and implementing the project.
For convenience of explanataion， the following discussion takes up a
“Land Improvement District" which commands such a wide area as
thousands ha of paddy fields and has had many years of history in paddy
field irrigation. “Land Improvement Districts" of such type have been
popular in each prefecture.
(2) Organization
Prior to the Agricultural Land Reform， only land owners were allowed
into the membership of an“Irrigation Association" or“Land Consolida-
tion Association"， and no tenant peasants were allowed to join. In the
case of a“Land Improvement District，" tenants， too， are allowed to join.
As a result of the Agricultural Land Reform， however， almost al1 farmers
have become land-holding farmers， and it may be said that al1 the members
of a“Land Improvement District" are land owners in the project area.
The director and trustees of a“Land Improvement District" are
elected by the farmers who are the members of the “Land Improvement
District."
A Land Improvement District with a wide command area (for exam-
ple， more than one thousand ha of paddy field) has its own office building
and full-time employees.
(3) Functions
Major functions of a Land Improvement District are as follows:
1. applies for a land improvement project，
- 36-
Re/ated Org，側 izations
2. repays project costs，
3. is responsible for operation and maintenance of major irrigation
and drainage facilities， such as main canals and laterals. But irrigation
canals below the tertiary canals or ditches are operated and maintained
by farmers of informal water users' groups. These groups are frequently
called “Mura"， and coincide with the smallest communities of farmers.
(4) Finance
Most of the construction costs of a project applied by a “Land Improve-
ment District" are， as mentioned before， subsidized by the government
and a prefecture. Contrary， the operation and maintenance costs， which
go to operate and maintain the irrigation and drainage facilities， personnel
costs， meeting expenses， c1erical expenses etc， are all covered by the fees
paid by the member farmers. Therefore， the membership fee may be
considered as the water charge.
The membership fee is determined not on the basis of the quantity of
water supplied from the irrigation facilities managed by a“Land Improve-
ment District，" but on the basis of the acreage of paddy field to which
water is supplied. A typical annual amount is fifty thousand yen per
hectare of padyy field， which is equivalent to 0.3 ton of paddy rice， or about
3% of total yield now in Japan.
The member farmers are in many cases obliged to work with no pay to
clean canals or to carry out maintemance work on tertiary or quartic
canals.
5-5 Education and research
(1) Type
In ]apan， six years of elementary school and three years of junior high
school are compulsory. Thereafter， there are three years of high school
and two years of junior college or four years of college. A number of
colleges have two years of master courses and additional three years of
- 37ー
Chapter 5
doctor courses. Land improvement engineering is being taught at a
number of colleges， junior colleges and agricultural high schools.
Information is given in Table 9.
Table 9 University and colleges (land improvement engineering oriented)
University Department Faculty
Adress members
Hokkaido Department of Agricutural 10 N9W9， Sapporo， University Engineering， Faculty of Agricul- 060
ture
Obihiro Department of 12 Inaba-cho， University of Agro-Environmentill Science Obihiro， 080 Agriculture and Veterinary Medicine
Kitasato Faculty of Engineering for 15 Towada， Aomori， University Animal Husbandry 034
Hirosaki Department of Agricultural 9 Bunkyo， Hirosaki， University System Engineering， Faculty of 036
Agriculture
Iwate Departmemt of Agricultural 14 Ueda， Morioka， University Engineering， Faculty of Agricul- 020
ture
Miyagi Agricul- Department of Agricultural 7 Hatadate， Sendai， tural College Engineering 982-02
The Akita Department of Agricultural 6 Ohgata-mura， Prefectural Engineering Akita， 010・04College of Agriculture
Yamagata Department of Bioenvironment， 12 Wakaba， University Faculty of Agriculture Tsuruoka，997
Ibaraki Division of Agricultural 9 3~21・ 1 ， Chuo， University and Environmental Engineer- Ami， Ibaraki， 300・03
ing， School of Agriculture
Utsunomiya Department fo Environmental 14 Mine， University Engineering， Faculty of Utsunomiya， 321
Agriculture
Chiba Division of Environmental (Division Matsudo， University Science and Landscape Archi- Members 24) Matsudo・city，271
tecture， Faculty of Horticulture 11
The University Department of Agricultural 16 Yayoi， Bunkyo， of Tokyo Engineering， Faculty of Tokyo，113
Agriculture
Tokyo Department of Agricultural 13 Fuchu， Tokyo， University of Engineering， Faculty of 183 Agriculture and Agriculture Technology
- 38-
Related Organizations
oUf nTivseurksuitby a， Institute of Agricultural and 8 Tsukuba，lbaraki， Forest Engineering 305
。T1f1oIlAkivgyeo rricsIutly ture Departmen t of A:五Cgurlitcultural 24 S叫Eurpzaygaa，oTkoak，yo EAnggriicnueletruirne g，Facu tyof Setagaya
156
Nihon Department of 。AlglErgiceuolftural 20 Kameino， University Enlrge 1naneed r1 ing，C Agricul- Fujisawa， 252
ture and Veterinary Medicine
MUneiijvi ersity De主Cpualrtt可mentof cAuglrtiucrue lture， 8 Higashimita， Faculty of Agri Tama， Kawasaki，
214
Shinsyu Department of Forest Science， 5 Minamiminowa， University Faculty of Agriculture Nagano，399-45
Niigata Department of Production and 19 9Ig5a0r.a2s1 hi，Niigata， University Environmen t Science，
Faculty of Agriculture
TProeyfaemcta ural DTeepchanrtomloegnyt ，oSf eActgioin cuof ltural 7 9K3o9s.u0g3 i，Toyama，
TICJOeIlIcllvh句uneosloiotfgyy ， Agricul tural Engineering
Ishikawa Department of Agricultural 9 Suematsu，
ACgolrliecgue ltural Engineering Nonoichi， Ishikawa， 921
Gifu University Department of Land and Water 9 Yanagido， Gifu，
EAgnrgiicnueletruirne g，Faculty of 501-11
Mie University DDFarecapuianlrtaty gme oef anBnt d ioof RreIemscoluagrmBctaeiots nio， n，
17 Kamihama， Tsu， 514
University of DReespoaurrtmcees nMt oaf nBagioelm句ein回t，lSch∞l
4 Hassaka-cho， Shiga Prefecture Hikone， 522
of Environmental Science
UKynoivto ersity Division of Science and 16 Kitashirakawa，
TEnecvhirnoonlomgeynotn ，GRrea4dduonatae l School 6S0a6k.y0o1 ，Kyoto，
of Agricul tural Science
Osaka Prefectural Department of RSecgieionncael ， 9 Sakai， Osaka予591University Environmental
Faculty of Agriculture
Kobe IDnefpoerrmtmateionn tof Environmental 13 Rokkodai -cho， University and Bio-Production Nada， Kobe， 657
Engineering， Faculty of Agriculture
Tottori DEAgnepgriamcruetlmetrueirnne gt ，oFf aAcgurlitcy uoltf ural
5 Minami 4・101，University Koyama-cho，
Tottori， 680
Department of Environmental 4 Minami 4・101，Science， Faculty of Agriculture
KTooYttaomria，d6810 0，
- 39-
Shiman巴University
Okayama University
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Kagawa University
Ehime University
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Miyazaki University
Kagoshima University
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Chapter 5
Arid Land Rese温rchCenter
Department of Regional Development， Faculty of Life and Environmental Science
Department of Agricultural Sciences， Faculty of Agriculture
Department of Environmental Management Engineering， Faculty of Environmental Science and Technology
Department of Environmental Sciences in Agriculture， Faculty of Agriculture
Department of Agricultural Engineering， Faculty of Agriculture
Department of Rural Engineering， College of Agricul ture
Department of Environmental Technology， Faculty of Agricul ture
Department of Agricultural Engineering， Faculty of Agricul ture
Course of Environmental and Information Engineering， Faculty of Agriculture
Agricultural Environment and Development Engineering Course
Department of Environmental Sciences and Technology， Faculty of Agriculture
Department of Agricultural Engineering， College of Agriculture
11
16
13
13
16
11
14
12
4 Hamasaka 1390， Tottori， 680
Nishikawazu， Matsue， 690
9
Tsushima-Naka， Okayama， 700
Tsushima-Naka， Okayama， 700
5 Yoshida， Yamaguchi，753
Miki-cho， Kagawa， 761-07
Tarumi， Matsuyama， 790
Monobe， Nankoku， 783
Hakozaki， Higashi-ku， Fukuoka， 812-81
Honjo， Saga， 840
9 Gakuenkibanadai Nishi 1・1，Miyazaki， 889-21
Korimoto， Kagoshima， 890
Nishihara， Okinawa， 903・01
(2) Organization of courses
With college， as an exarnple， the organization of a standard course is
introduced.
Most]apanese colleges have sorne“Faculty" to cover specified fields of
science or engineering. Many colleges or “Faculties" of agriculture have
- 40ー
Related Organizations
a department or course to teach land improvement tengineering. Faculty
members are professors， associate professors and assistant professors.
A typical classification of land improvement engineering in college，
from a viewpoint of teaching and research， is as follows:
1. Water.related technologies:
Hydraulics， hydrology， hydraulic design of hydraulic structures such
as dams and canals， applied hydraulics， appplied hydrology， and planning
of irrigation and drainage projects.
2. Soil-or earth-related technologies
Soil physics， soil mechanichs， earth works for reclamation of agricul-
turalland or for land consolidation， improvement of soil property by earth
works.
3. Civil engineering-or design/construction-related technology
Applied mechanics， structural mechanics， properties and usage of
materials such as concrete.
At a number of colleges， some organizational modifications have been
effected recently. Prior to such modifications， many colleges had a
“Department of Agricultural Engineering"， consisting of four units of
teaching and research， with the addition of a unit for agricultural machin-
ery to the three units described above.
(3) Curriculum
A typical curriculum to teach land improvement engineering at a
college is as follows.
Classroom teaching is almost exclusively in Japanese. Textbooks
and references books are also mostly in Japanese. Some faculty teach
foreign students in English personally and informally accoding to
C1rcumstances.
(4) Employment
After graduation from college the graduate may:
1. take a national examination or a prefectural examination to
- 41-
Chapter 5
become a government official and work as a land improvement engineer
for the Agricultural Structure Improvement Bureau in the Ministry of
Agriculture， Forestry and Fisheries， or in the prefectural Section of Land
Improvement Project.
2. join a private company， either construction or consulting.
3. work for a public corporation as an engineer， or teach at an
agricultural high school， or work at a private company in a different field.
Others may join a graduate course to become a professor， a researcher， or
an executIve engmeer.
(5) Graduate schools
Graduate students get more advanced education， and conduct
research to write a masters thesis or dissertation.
(6) Foreign students
These col1eges and graduate schools accept a number of foreign
students. Many of them are on scholarship from the Japanese govern-
ment. Some are on their own government scholarship， and others are on
their own.
The minimum years of schooling are， like Japanese students， four
years of col1ege after graduation from high school， two years of masters
course， and three more years of doctors course.
(7) J unior colleges and high schools
Education being offered at and studies being made at junior colleges
are almost the same as those at colleges.
In Japan， most high schools are regular high schools. There are also
high schools of engineering， comrnerce and agriculture. Only a few
agricultural high schools offer courses on land improvement engineering.
The subjects they offer are similar to those offered at col1eges introduced
above.
(8) Special research institutions attached to colleges
Some colleges have a research institute which are predominantly
- 42-
Related Organizations
involved in overseas regional problems in a land improvement engineering
field:
1. Kyoto University Southeast Asia Research Center
The Center was established in 1965 to conduct comprehensive studies
on the developing countries， especially Southeast Asia. Its studies are
more comprehensive than simple regional studies， as they cover studies in
the field of natural and social sciences. The Center has an office both in
Bangkok and Jakarta where researchers are always stationed.
Table 10 National Research Institute of Agricultural Engineering
Director General Research Planning and Co-ordination Division Department of General Administration Dept. of Rural Improvement
Laboratory of Rural Planning Laboratory of Rural Settlement Planning Laboratory of Aquatic Environment Conservation Laboratory of Rural Sewage Laboratory of Operation and Management System
Dept. of Regional Resources Laboratory of Hydrology and Water Resources Laboratory of Groundwater Resources Laboratory of Land Resources Laboratory of R巴gionalEnergy Resources
Dept. of Land Improvement Laboratory of Paddy Fields Soil and Water Laboratory of Field Irrigation Laboratory of Multi-purpose Fields Management Laboratory of Land Reclamation and Conservation Laboratory of Structure and Material in Agrciultural Buildings Laboratory of Environmental Control in Agrciultural Buildings
Dept. of Hydraulic Engineering Laboratory of Water Management System Laboratory of Dams and Headworks Hydraulics Laboratory of Canal Hydraulics Laboratory of River and Coastal Engineering Laboratory of Hydrodynamic Control and Analysis
Dept. of Structural Engineering Laboratory of Structures Analysis Laboratory of Construction Materials Laboratory of Soil Engineering Laboratory of Engineering Geology
Adress: 1・2，Kannondai 2-chome， Tsukuba， Ibaraki， 305
- 43-
Chゆte:γ5
2. Tottori University Arid Land Research Center
The Insti tu te was esta bished in 1958. In addi tion to the studies of
sandhill， studies of agriculture in semi-arid and arid region， are being
made.
5・6 National Research Institute of Agricutural Engineering
This is the Ministry of Agriculture， Forestry and Fisheries' research
institute for study of land improvement engineering.
Its organization is shown in Table 10.
The Institute conducts studies to solve various problems which may
occur when planning a land improvement project， or designing and/or
constructing facilities for the project; it also studies various problems
which may develop. The 1995 budget was about 1，586 million yen，
including research funds on commission.
5・7 Other research and experiment institutes
Land improvement engineers also work for other governmental or
prefectural research or experiment institutes， in addition to the research
institutes described above.
National Institute of Agro. Environmental Sciences
3，486 million yen， 220 staff and technicians
National Agriculture Research Center
5，958 million yen， 319 staff and technicians
National Research Institute of Fisheries Engineering
823 million yen， 62 staff and technicians
- 44-
Chαpteγ6
International Cooperation
6-1 International academic societies
The members of the ]apanese Society of Irrigation， Drainage and
Reclamation Engineering join international academic societies as well as
domestic ones in their respective fields. They also attend international
conferences.
(1) International Commission of Irrigation and Drainage (ICID)
The ICID has a membership of 80 countries including Japan. A
number of members of the ]apanese Society of Irrigation， Drainage and
Reclamation Engineering are active members of ICID. The secretariat of
the domestic committee is an executive official of the Agricultural Struc-
ture Improvement Bureau， Ministry of Agriculture， Forestry and Fisher-
ies. The secretariat of the domestic organization， to support the activities
of the domestic committee， is within the ]apanese Institute of Irrigation
and Drainage OIID). Some ]apanese professors and engineers attend the
general conference of ICID and its various meetings and task force
meetings.
The address of the]apanese domestic committee is:
c/o ]IID. Toranomon NN Bi1ding， 1-21・17，Toranomon， Minato-ku， Tokyo
6・2 Official Development Assistance (ODA)
As the developing countries do not have sufficient capital， technologi-
cal and human resources， the developed and industrialized countries
cooperate to supplement such deficiencies. Such cooperation is generally
- 45-
Chapter 6
called economic cooperation. Funds for economic cooperation channeled
into the developing countries may be c1assified into the following four
groups， according to the DAC: (1) official development assistance， (2) other
official f10ws of government funds， (3) flow of private funds， (4) donation
by private and non-profit organizations.
As ODA， there are country-to圃country(bilateral) donations， contribu.
tions and financing to international organizations and government loans
between two countries. As for country-to・countrydonations， there are
free financial cooperation and technological cooperation.
(A) ]ICA Qapan International Cooperation Agency)
(1) Organization
]ICA， established in 1974， is an official agency which is responsible for
the technical cooperation aspect of ]apan ODA programs. The headquat-
ers are in Tokyo， and have sections as shown in Table 11. ]lCA has
established 73 overseas offices in 71 countries as stated in Table 11. It
has also a number of affiliated organs and branch offices in ]apan，
including Tukuba International Agricultural Training Center， and Insti-
tute for International Cooperation.
Table 11 Japan International Cooperation Agency aICA)
Japan International Cooperation Agency: Shinjuku Mitsui Bldg.， 2.1-1， Nishi-Shinjuku， Shinjuku-ku， Tokyo
Secretariat of Japan Overseas Cooperation Volunteers aOCV): 4.2.24， Hiroo， Shibuya-ku， Tokyo
Tsukuba International Center: 3-6， Koyadai， Tsukuba-shi， Ibaraki-ken くASIA)Bangladesh: Brunei:
Cambodia: China:
India:
Indonesia: Malaysia:
Myanmar:
Plot No. N羽T(c)l，Road No. 62163， Gulshan， Dhaka.12ロ，Bangladesh No. 6， Simpang 80-45， Kg. Pengkalan Gadong， Bandar Seri Begawan， Negara Brunei Darussalam House No. 157， Street No. 71， Phnom Penh， Cambodia Room No. 1111， Beijing Fortune Building 5， Dong San Huan Bei-Lu， Chao Yang District， Beijing 100004， People's Republic of China 2nd Floor， DLF Centre， Sansad Marg (Parliament Street) New Delhi-110001，lndia JI. M. H. Thamrin 59， Jakarta Pusat， Indonesia Suite 18.1W， 18th Floor， Wisma Sime Darby， Jalan Raja Laut 50350， Kuala Lumpur， Malaysia Technical Cooperation Section， Embassy of Japan， No. 17， University Avenue， Yangon， Myanmar
- 46-
Tripureshore， Kathmandu， Nepal House No.1 St. No. 61， F・6/3，Islamabad， Pakistan 12th Floor， Pacific Star Building， Senator Gil J. Puyat Avenue， Extension Corner， Makati Avenue， Makati， Metro Mania， Philippines Room 801， RELC Building 30， Orange Grove Road， Singapore， 1025 Hotel Taj Samudra 6th floor， 25 Galle Face Centre Road， Kollupitiya， Colombo 3， Sri Lanka
Thailand: 1674/1 New Petchburi Road， Bangkok 10310， Thailand くMIDDLEEAST> Egypt: World Trade Center 10th Floor 1191 Comiche El Nile St. Boulak， Cairo，
Arab Rep. of Egypt 18， Al・Mutanabbi，Jabal Amman， Amman， Jordan BUREAU DE LA JICA AU MAROC， 28， Rue Beui Boufrah， Lotissement Ghandouri， Souissi， Rabat， Maroc
Saudi Arabia: Japanese Embassy Premises Diplomatic Quarter， Riyadh， Saudi Arabia Syria: Al・AqaadBuilding， 3574 Sharkashiah， Abdul Kader AI-Jazaeri， Abouro・
maneh， Damascus， Syria BUREAU DE LA JICA EN TUNISIE， 18， Rue Ahmed Rami 1002 Tunis-Belvedere， Tunisie
くAFRICA>Cote d'lvoire: Boulevard Carde， Des Bureaux， A L'lmmeuble les・Harmonies，M1 6eme
Etage， Abidjan Plateau， Cote d'lvoire House No. 1163， Kebele 08， Wor吋 a23， Addis Ababa， Ethiopia B182， North Labone， Accra， Ghana Utumishi Co-op House， 3rd Floor， Mamlaka Road， Nairobi， Kenya Area 13-Plots 5 and 6， Lilongwe 3， Malawi Cowrie House， Plot 27/29 Adeyemo Alakija Street， Victoria Island， Lagos， Nigeria BUREAU DE LA JICA AU SENEGAL， Immeuble SDIH， 3， Place de l'lndependance， Dakar， Senegal
Tanzania: Plot No. 28， Kingsway Estate， Bagamoyo Road， Dar es Salaam， Tanzania Zambia: Plot No. 59B Mutandwa Road， Roma， Lusaka， Zambia くSENTRALAND SOUTH AMERICA> Argentina: AGENCIA DE COOPERACION INTERNACIONAL DEL JAPON， Dr.
Ricardo Rojas 401， Piso 8， 1001・BuenosAires， Argentina AGENCIA DE COOPERACION INTERNACIONAL DEL JAPON EN BOLIVIA， Final Avenida 20 de Octubre No. 2689， La Paz， Bolivia ESCRITORIO ANEXO DA EMBAlXADA DO JAPAO， Scs Quadra 01， Bloco F， Ed， Camargo Correa， 12<? Andar， Brasilia， Brasil ESCRITORIO ANEXO DO CONSULADO GERAL DO jAPAO EM SAO PAULO， Rua Saojoaquim， 381-6 Andar， Liberdade， SaoPaulo， Estado de SaるPauloAGENCIA DE COOPERACION INTERNACIONAL DEL jAPON， Av. Anderes Bello 2777， Piso 27， of 2701， Providencia， Santiago， Chile AGENCIA DE COOPERACION INTERNACIONAL DEL jAPON， Cal1e 72， No. 10・07，Piso 7， Santa Fe de Bogota， Colombia AGENCIA DE COOPERACION INTERNACIONAL DEL jAPON， Av. Bolivar No. 818， Santo Domingo， Republica Dominicana MISION TECNICA DEL jAPON， Calle Santa Rosa， Colonia Lomas Del Mayab， Case Nヲ1346，Tegucigalpa， M. D. C.， Honduras Aristoteles 77-403， Chapultepec Morales， Mexico， D.F. 11560 AGENCIA DE COOPERACION INTERNACIONAL DEL JAPON EN PANAMA， Torre Swiss Bank， Calle 53ヲUrbanizacion Marbella， Panama AGENCIA DE COOPERACION INTERNACIONAL DEL jAPON OFIC-INA EXTERIOR EN PARAGUAY， Presidente Franco Y Ayolas， Edificio A.yfra 11 <? Piso， Asuncion， Republica del Paraguay
Nepal: Pakistan: Phili ppines:
Singapore: Sri Lanka:
Jordan: Morocco:
Tunisia:
Ethiopia: Ghana: Kenya: Malawi: Nigeria:
Senegal:
Bolivia:
Brazil:
SaoPaulo:
Chile:
Colombia:
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Mexico: Panama:
Paraguay:
I抗teγnatioγzalCoo争eγation
- 47-
Chapter 6
Peru: AGENCIA DE COOPERACION INTERNACIONAL DEL jAPON， Av. Angamos Oeste 1381， Santa Cruz， Miraflores， Lima， Peru
くOCEANIA>Australia: Level16， AMP Center， 50 Bridge Street， Sydney 2000， Australia Fiji: 3rd Floor， Dominion House， Suva， F司iPapua Shop 7 A， Second Floor， Garden City， Lot 4， Section 18， Angau Drive， New Guinea: Boroko， N.C.D.， Papua New Guinea Western Samoa: Mulivai， Apia， Western Samoa <OTHERS> Austria: Prinz Eugen Strasse 8 (Wohlleben Gasse 3-5) 1040 Wien， Austria Canada: ANNEX OFFICE， CONSULATE GENERAL OF jAPAN AT TORONTO，
National Bank Building， 150 York 5treet， Suite 1120， Toronto， Ontario， Canada， M5H 355
France: BUREAU DE jICA EN FRANCE， 4-8， Rue 5ainte-Anne， 75001 Paris， France
U.K.: 45 Old Bond 5t_， London W1X 2AQ， U. K. U.S.A.: 900 19th 5treet， N. W.， Suite 350， Washington， D. C. 20006. U. 5. A.
(2) Services
Technical cooperation is the main service of JICA， and aimed at
transfer of technology and knowledge that serve socio-economic develop胆
ment of the developing countries. ]ICA carries out variety of programs to
support nation building of the developing countries through such technical
cooperation.
]ICA has about 1，200 staff menbers working both in ]apan and at its
overseas offices.
JICA's program include;
1) Technical Cooperation
. Training in ]apan
. Dispatch of Experts
. Provision of Equipment
. Project-type Technical Cooperation
. Development Study
2) Dispatch of ]apan Overseas Cooperation VolunteersGOCV)
3) Training and Recruitment of Qualified Personnel for Technical
Cooperation
4) Survey and Administration of Grant Aid Programs
5) Development Investment and Financing
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1 nternational Cooperation
6) Support for ]apanese Emigrants
7) Disaster Relief
]ICA's Budget amounts to 169，248 million yen in fiscal 1995， and all
budget come from the national government.
Durii1g fiscal 1994， ]ICA accepted 8，834 trainees， dispatched 3，046
experts， 6，004 members of missions， and 2，410 overseas cooperation volun-
teers， and offered 5，540 million yen for grant aid assistance programs.
(B) Overseas Economic Cooperation Fund (OECF)
(1) Organization
The OECF was established in 1961. It has seven departments， two
offices and twelve overseas representative offices.
It has 248 employees. All its funds come from the national government.
(2) Services
The major services of the OECF may be classified into the following
three categories:
1. direct loan: loans to foreign governments， including local public
corporations and local governments.
2. general projects: loans to and equity investment in ]apanese
corporations engaged in development projects overseas.
3. cooperation with other donator organizations: contribution to
buffer stock under international commodity agreeement.
In addition to the aforementioned services， it conducts post-evaluation
to confirm whether the expected effects have been realized. It has also
started to conduct surveys and plan modifications to promote realization of
proj ect effects.
Land improvement engineers participate in these services of OECF，
too.
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Chapter 6
6・3 Japanese embassies and international organizations
(1) Overseas， ]apanese engineers from the Agricultural Structure
Improvement Bureau are working as attaches at ]apanese embassies.
They are working as intermediates for matters related to agriculture，
forestry and fishesries between ]apan and the country where they work.
Currently， land improvement engineers of the Ministry of Agriculture，
Forestry and Fisheries are working as attaches at the ]apanese embassies
shown in Table 12.
Table 12 Japanese embassies with in-house land improvement engineers
Philippines: 375， Sen. Giリ.Puyat Ave. Makati Metro Manila， Philippines Thailand: 1674， New Petchburi Rd. Bangkok， 10310， Thailand Cambodia: No， Moha Vithei Preah Norodom， Sangkat Phsar Thmey 3 Khan Don
Myanmar: Viet Nam:
Sri Lanka:
Pakistan: China: Egypt:
Bangladesh:
Turkey: Colombia: Chile: N etherlands: Poland: U.S.A.:
Dominica:
Honduras:
Bolivia: Ivory Coast:
Tanzania: Zimbabwe:
Nepal:
Penh， Phnom CAMBODIA NO.100. Natmauk Road， Yangon MYANMAR No. 61 Truong Chinh Road， Phuong Quarter Dong Da District， Hanoi， Socialist Republic of Viet Nam No. 20， Grモgory'sRoad， Colombo 7， Democratic Socialist Republic of Sri Lanka Plot No.53-70， Ramna 5/4 Diplomatic Encave 1， Islamabad， Pakistan 7， Ri Tan Road， Jian Guo Mei Wai， Beijing， People's Republic of China 3rd floor， Cairo Center Building， 2， Abdel Kader Hamzza Street， Garden City， Cairo， Arab Republic of Egypt Plot No. 110， Road No. 27， Block-A， Banami Model Town， Dhaka， 13， Bangladesh Resit Galip Caddesi 81， Gaziosmanpasa， Ankara， Turkey Carrera， No. 74-21， (Piso-8) Edificio Seguros Aurora， Bogota， Colombia Av. Providencia 2653， 19-Piso， Casilla 2877， Santiago， Chile Tobias Asserlaan 2， 2517 KC， The Hague， The Netherlands Ul. Willowa 7. Warsaw， Poland (Consulate general of ]apan at San Francisco) 50， Fremont Street， 23rd Fl∞r， San Francisco， California 94105， U. S. A. Torre BHD， 8 Piso Avenida Wiston Churchill， Esquina Luis F. Thomen， Santo Domingo， Republica Dominicana Segunda Avenida， Frente Plazoleta del Arobol de Guanacaste， Colonia Reforma Tegucigalp也， D. c.， Honduras， C. A. Calle Rosendo Gutierrez No. 497， esq. Sanchez Lima， La Paz， BOLIVIA Immeuble Alpha 2000 Tour Al 8eme Eyage， Avenue Chardy， Abidjan， Cote d' Ivひire(01 B. P. 1329， Abidjan 01) Plot No. 1018， Upanga， Dar Es Salaam， TANZANIA 18th Floor， Karigamombe Centre， 53 Samora Machel Avenue Harare， ZIMBABWE Panipokhari， Kathmandu， Nepal
(2) International organizations
]apanese land improvement engineers are also working for FAO，
InteγねatioηalCooμγatio汎
(headquartered in Rome with Asian regional offices in Bangkok) the Asian
Development Bank in Philippine， International Irrigation Management
Institute in Sri Lanka， Asian Institute of Technology in Tahiland， and
many other similar international organizations.
6.4 Agricultural Development Consulting Association (ADCA)
ADCA was established in 1977 with the guidance of the Ministry of
Agriculture， Forestry amd Fisheries. Its members are those of consulting
companies and others which are strongly interested in overseas agricultu-
ral development and have an intensive will to participate in it. As of
1986， forty seven companies， including manufacturing and trading com-
panies， and twenty two consulting companies are supporting members.
The Association is actively conducting project finding surveys， sur-
veys for master plans and feasibility studies for overseas agricultural
developmen t in such land im provemen t -orien ted fields as developmen t of
water resources， reclamation of agriculturalland， agriculturalland consol-
idation， irrigation and surface-and subsurface-drainage， integrated rural
planning， and studies and extension of agricultural development
technologies.
6・5 Tropical Agriculture Research Center
The Ministry of Agriculture， Forestry and Fisheries has about thirty
research institutes. The Tropical Agriculture Research Center was
established in 1970 as a liaison for overseas studies. As of 1986， 95
researchers were working for the Center. They are studying agriculture
and forestry of tropical and sub-tropical zones.
6圃 6 Others
]ALDA Gapanese Agricultural Land Development Agency) began to
conduct agriculturalland development projects overseas in 1982， and the
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chapter 6
]IID Gapanese Institute of Irrigation and Drainage)， established in 1978，
has also such functions as acceptance of trainees， drawing up of technical
manuals， etc.
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Chα争teγ7
Paddy
Paddy rice is a major crop in Japanese agriculture， the most popular
profitable crop for farmers to grow， and occupies the widest acreage of
agriculturalland among all crops inJapan， and has been and sti11 is staple
food for Japanese.
7.1 Varieties
The paddy rice varieties being grown in Japan are not the Indica
varieties， which are internationally popular， but the Japonica varieties，
grains of which are short， roundish， sticky and sweet.
Owing to efforts of the past several decades to improve varieties，
mainly at government experiment centers， more than ten tons of paddy
4
3
2
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z一コυ
， ， ， ， ， ， ， ， J ， ，
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-vy
，
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q-du --a
pnv
困
-
、‘阿川
、町
O、n
「'F守‘F
V
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it』
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1000 1950 1980
Figure 5 Agriculturalland.
- 53-
Chapteγ7
yield per hectare can be harvested nowadays. A number of modern
varieties， i.e.， high yielding varieties， have been developed. Also， low-
temperature resistant varieties have been developed.
Today， farmers wish to have varieties which taste best to consumers，
even though the yield is less， and studies are progressing to develop such
varieties.
7・2 Increase against time in paddy field and rice yield
Both acreage of paddy field and average rice yield have increased year
after year up to now.
Generally， yield is represesnted in terms of brown rice yield in Japan，
though it is expressed by paddy yield internationally. The unit conver-
sion coefficient is a little over sixty percent.*
*Japanese farmers express yield， using a peculiar domestic measurement unit “hyo" t in terms of hyo/1000 m2• A hyo of rice is equivalent to 60 kg of unhusked brown rice， the number of“hyo"， harvested from a paddy field of 1000 m2 is directly converted to paddy yield which is expressed by ton/ha.
7・3 Reasons for increased yield
During the past one hundred years， the paddy yield of rice has
achieved a drastic increase from 4 ton/ha to 10 ton/ha. And the following
three reasons might be pointed out:
1. Improved quality and function of agricultural chemicals such as
fertilizers and pesticides， as well as increased application.
2. The efforts to modify and improve varieties have produced those
varieties which are not collapsed by a heavy application of fertilizers and
produce a higher yield. Moreover， varieties， which may be grown in low
temperature areas of the north， and which are highly resistant to low
temperatures， have been developed， resulting in an increased area where
paddy rice may be grown.
3. The effects of land improvement projects may be pointed out. Loss
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Paddy
of paddy rice production due to water shortage in years with insufficient
rainfall， and also 10ss caused by floods with heavy rainfall has been
reduced owing to irrigataion and surface drainage projects. A1so， subsur-
face drainage projects have succeeded in 10wering the groundwater level
and thus in improving soil conditions. Land consolidation projects have
been effective for improving water management at the farm and plot 1evel.
With the progress of civil engineering and 1and improvement projects，
which here means to reclaim virgin 1and so as to deve10p new paddy fie1ds
and to construct irrigation facilities such as dams and canals， the total
area of paddy fields increased. Theses 1and improvement projects have
been implemented through government subsidies and farmers' self
support.
7・4 Agricultural inputs
An average app1ication of agricultura1 inp，uts in rice growing in ]apan
in 1993 was:
fertilizer
nitrogen N: 85.4 kg/ha
phosphorus P205: 94.0 kg/ha
kalium K20: 81.7 kg/ha
7・5 Food control system， demand for and supply of rice
During the Second World War， the national government established a
system to purchase rice at the price set by the goverriment from farmers
and to supp1y it to consumers at an inexpensive price in order to secure a
stable supp1y of rice.
With an increase in rice production after the War， the actual functions
of the system have undergone changes. The government always pur-
chases the rice produced by farmers at a specific price. Moreover， the
government purchasing price is so calcu1ated to guarantee farmers the
- 55-
Cha:争te;γ7
production costs including their living costs. This high purchasing price
has encouraged farmers to grow rice， and rice production has increased.
Meanwhile， consumer taste has changed for food， and rice consumption
has decreased. As a result， the demand-supply balance for rice has been
disturbed， and rice has become excessive.
7圃 6 Excessive production， reduction of planting field， well-
drained paddy field
The difference between the selling and purchasing price of rice， which
is 'contolled by the government， are made up for from the national budget.
As this make-up amount has become enormous， the government has
limited the amount of rice to be purchased at the specified price. Even
with this， excessive production of rice has not stopped， and the govern-
ment has asked farmers not to grow rice in some of their paddy fields.
The farmers unwillingly responded to the request. This is called “reduc-
ing planting paddy field". The farmers who did not grow rice in coopera-
tion with this policy received subsidies according to the area of field not
used to grow rice. In 1988， the area of paddy fields where no rice was
grown amounted to 27% of total paddy fields.
For increasing croping intensity， it is desirable to grow crops other
than rice， including wheat and vegetables， in the paddy fields. In order to
grow such crops other than rice， drainage of paddy fields must be
improved. Those paddy fields with improved drainage to allow produc-
tion of any crop are called “(well-drained) field to be able to grow non-
paddy crop as well as paddy rice". They are provided with subsurface
drains and/or open channel drains for better drainage.
7・7 Mobilization of agriculturalland
The majority of ]apanese rice growing farmers have jobs other tha，n
farming. A considerable proportion of these farmers have no successors
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Paddy
to continue farming. Even today， some farmers lend to other farmers
their paddy fields. japanese farmers think it is wise management of their
assets to continue to hold their farming land， instead of selling it. As a
result， transaction of agriculturalland is very rare， and when it is sold， its
price is very high. As the rent is relatively low， those farmers wishing to
increase their cultivating area choose to do so by borrowing land. As the
japanese rice production cost is considerably high in international compar-
ison， the government has been working hard to reduce the cost. This
expanding cultivating area by borrwing land has a merit of improving
labor and capital productivity， and reducing rice production costs. The
government， therefore， encourages such lending and borrowing of agricul-
turalland， calling it“mobilization" .
ヴ
tE1U
Chα争teγ8
Miscellaneous
8・1 Agricultural machinery
J apanese farmers who have become land-holding farmers as a result of
the Agricultural Land Reform wished to improve labor productivitiy， in
addition to the improvement of land productivity. Agricultural machin-
ery of many types have come to be used in large number (prior to the
Second World War， almost no agricultural machinery was used.) In
paddy fields， small walking-type tractors were first used. Subsequently，
relatively large tractors (30 to 50 horse power) were introduced. Then，
combines suitable for paddy rice harvesting were developed and spread.
As for rice transplantation， which is a bottle neck as it requires the most
intense amount of labor， transplanting machines have been developed， and
the problem: of labor peak period has been solved to some extent.
For non-paddy crops， orchards， and green houses， too， a number of
machines and equipment have been introduced.
The following are statistics of machines owned by farmers: trans-
planting machinery for paddy: 50.9 sets/100 farmers' households， combine
for paddy: 29.8 sets/100 farmers' households， tracter (larger than 15 HP):
33.9 sets/100 farmers' households.
8・2 Irrigation projects for non-paddy crops
In the global scene， irrigation for non-paddy crops is the mainstream..
In Japan， irrigation for paddy rice has been implemented for all paddy
fields. The first irrigation project for non-paddy crops was done only
after the Second Wor1d War， however. Prior to that， Japanese agricultu・
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M iscellaneous
ralland， other than paddy field， was entirely rain-fed. After'the war， the
first large-scale irrigation project for non-paddy crops was started in
Kanagawa Prefecture， next to Tokyo. It was a furrow irrigation project
to provide facilities for vetables and crops. But the facilities were lost
because expansion of the Tokyo urban area led to conversion of agricultu-
ralland to housing land.
Later， irrigation by sprinklers started at mandarin orange orchards.
It was discovered， however， that in Japan， whichis situated in the humid
region， the number of days requiring supplemental irrigation to make up
water for soil moisture deficit in mandarin orange orchards during a dry
spell is extremly limited. In order to increase the frequency of using
sprinklers， they were used to apply pesticides dissolved in water. This
method has not only reduced the work of farmers but also has been
preferable from the standpoint of farmers health， i.e.， prevention of intoxi-
cation from pesticide.
In the irrigation ditricts of the Toyokawa Water Supply Systems，
trickle or drip irrigation within green houses has become popular， together
with the sprinkling method.
As mentioned above， world popular irrigation methods such as furrow
or basin irrigation methods are being rarely used in Japan.
Irrigation facilities are also being used for purposes other than appli-
cation of pesticides. For instance， they are used to prevent damage from
cold and frost， and to protect wind erosion caused by strong winds.
Irrigation facilities are being effective for diversifying crops， in addition to
supplying water to moisture deficient soil due to drought. With construc-
tion of irrigation facilities， farmers start to grow vegetables， fruits and
flowers which are less-drought resistant， but which are more profitable，
instead of past crops and vegetables which are highly drought-resistant
but less profitable.
For construction of such irrigation facilities， the government and
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Cha;争te-γ8
prefectures provide subsidies. Operation and maintenance costs are paid
by the farmers themselves.
8・3 Earth works in reclamation projects
The majority of japanese agricultural land is paddy fields which，
unlike other types of non-paddy agricultural land， require land leveling
and construction of embankment and ditches for irrigation and drainage.
As a result， japanese land improvement engineers are highly experienced
in works handling an enormous amount of earth to reclaim agricultural
land， not seen in Europe or in the U.S.A. For reclamation or land
consolidation projects， such engineering methods as will return fertile
surface soil onto the agriculturalland， level the surface with a proper scale
with minimum moving volume of soil， make a too permeable soillayer (like
a volcanic ash soi11ayer) less permeable by constructing an less permeable
soil layer beneath the surface layer and then cultivated skillfully using
civil engineering machineries to develop a paddy field with less percola-
tion， have been developed.
Such excellent earth work technologies are being appplied to cultivate
steep-sloped land to develop fields， orchards or pastures.
8-4 Projects of reclamation from.sea or lake bottom
In japan， like in the Netherlands， parts of estuaries， lakes and bays
have been reclamied to develop new paddy fields. Today， with excessive
prod uction of rice， i t has become less necessary to reclaim land to increase
paddy fields， and there are also less candidate land areas for reclamation，
resulting from higher reclamation costs. There are also problems of
natural conservation. Presently， therefore， only a few reclamation pro-
jects. are progressing.
japanese land improvement engineers have， however，produced 34，700
hectares of agriculturalland through reclamation projects such as， includ-
- 60-
Miscella悦 'ous
sea
dike
sea←ー
polder
(叫agr円l悶cuturalland
pump station
lake (fresh water)
Figure 6 Sea bottom reclamation double dike system.
ing only those carried out after the Second World War， Hachirogata
(15，800 ha) and Kojima Bay (1，060 ha)， utilizing not only those technologies
learnt from the Netherlands but also the state-of-art technogies of the
time. Thus， ]apanese land improvement engineers have shown positive
achievements in a numher of rec1amation projects， and have accumulated
- 61ー
Chゆteγ8
know-how of reclamation technologies.
In recent years， a number of projects have been completed， in which
double dikes were constructed in a bay or lake to replace the seawater
between the dikes with runoff flowing into it to creat an“artificial fresh
water lake". This water will be used as an irrigation water resources for
newly reclamated agricultural land created through the reclamation
pr句ect.
8・5 Disaster prevention projects
When agricultural facilities such as diversion dams， bridges， pumping
stations and canals are destroyed or agricultural land is darnaged by
floods， land slides or other natural disasters， they wil1 be repaired or the
facilities will be reconstructed. In that case， almost all of the construc-
tion costs will be paid by the government (92"""'95%). In 1987， such costs
amounted to 64.8 billion yen.
8・6 Projects related to water and soil pollution
The Agricultural Structure Improvement Bureau also provides a
menu .of land improvement projects for water- and soil-quality
conservatlon.
In rapidly urabanizing districts， plants and houses have been con-
structed and waste discharged from them have flowed into irrigation
canals to pol1ute irrigation water. When this water pollution exceeds the
specified level (1 ppm for nitrogen concentration， for instance)， that
district will be qualified to get an implementaion of water pollution
counter-measure project and the government and the prefecture will pay
the project costs. The farmers will usually not be required to pay any of
the costs.
When the soil is polluted with Hs (arsenic) discharged from factories，
a project of a different kind will be implemented. In this case， the
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M iscellaneous
polluting factory wil1 be required to pay some part of the costs. No farmers
will be required to pay.
8開 7 Community sewerage systems and other infrastructures
Recent land improvement projects in ]apan have expanded their
coverage from the past projects for developing agricultural production to
develop such infrastrucures as dams， canals， farm roads， reclamation of
land， consolidation of agriculturalland， etc. to projects to develop infras-
tructures for living in agricultural villages.
The typical case is a project called “Community Sewerage Project" .
It constructs a sewerage system to col1ect sewage from the community and
treat it. Since 1963 up to 1987， 152 systems， covering 93，000 people， have
been constructed in rural communities.
In addition， community roads， meeting halls， parks etc. have been
constructed in rural communities through this new project menu.
8・8 Concept of irrigation water requirement for paddy
To construct an irrigation system for paddy， the capacity requirement
of irrigation facilities has to be estimated. In the authorized manual used
for land improvement projects in ]apan， the components of capacity
requirement are as follows:
The water requirement for a paddy plot is the sum of the evapotrans-
piration which is the total of the evaporation from the surface of ponded
water in the plot， transpiration from rice plants， and deep percolation.
This sums is called by the special term of “Gensuishin" in ]apanese，
which means“decrease of water depth". The sum may be measured
from the reduction of ponded water in the plot.
The water requirement obtained by substracting“the designed effec-
tive rainfall" to be expected in“the design year" from the aforementioned
sum is a net requirement. Then， a loss of 15% is normally added to this
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Chapter 8
net requirement to get a gross water requirement， i.e.， diversion require-
ment. This figure of 15% may appear too small in view of actual condi-
tions， but the diversion requirement will coincide with the actual water
requirement， as experienced irrigation engineers estimate the net require-
ment， taking into consideration the actual conditions in the project area.
The diversion requirement for paddy in ]apan ranges at maximum
from 10 to 80 mm/day during the growing stage， but typically from 20 to
30 mm/day. During the paddling and transplanting stage， 100 to 150
mm of water is considered necessary. The design year is so selected that
the rainfall during the design year may be less than that to be encountered
once every ten years， calculating from the past records of rainfall in the
project district. The effective rainfall during the year is calculated from
the rainfall during the design year according to established rules autho-
rized by the Bureau. In ]apan， not only the Ministry of Agriculture，
Forestry and Fisheries but also all ministries and agencies concerned with
water supply， including the Ministry of Construction adopt the drought
year to be encountered with above-stated probability “design year".
8・9 W ater management under a paddy irrigation system
(1) On-farm water management
To irrigate the paddy plants growing in a paddy field， the water
diverted， for instance， into paddy fields of several hundreds or several
thousands or more has to be distributed through a long and complex
network of waterways at uncountable numbers of distribution points， and
the necessary amount of water has to be delivered when needed. Espe-
cially in a dry spell， it would be different to fairly and certainly distribute
the scarce water to a large number of farmers. In ]apan， such on-farm
water management is performed by a Land Improvement District or
voluntary groups of farmers which are a sub-organization of a Land
Improvement District， distributing water through the tertiary canals and
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Miscellaneous
farm ditches intensively distributed.
In ]apan， popular paddy irrigation systems are such that the water
diverted from the river is delivered to all the canals and to all the plots in
command area both simultaneously and continuously.
In ]apan， too， a large number of tanks or ponds have been constructed
in the districts where avai1able water may be scarce due to insufficient
rainfall during the irrigation season. In such districts， and even in those
districts where enough water can be diverted from the river in normal
years， irrigation is done on a rotaional basis by canals or by paddy plot in a
drought year with water shortage.
(2) On-plot water management
To realize a paddy yield of more than 10 ton/ha， such water manage-
ment is necessary to drain the water above the ground level to dry the soil
to some extent for aeration， instead of leaving the water in the plot to make
it a pond.
8・10Water rights: progress of urbanization and diversion of
water rights
The economic growth and progress of urbanization after the Second
Wor1d War have caused diversion of a large number of paddy fields into
housing， office or factory land lots. As a result， it was thought best to
divert some of the water for irrigation to water for the newly born cities.
In]apan， however， an approval from the Ministry of Construction has
to be obtained under the River Law to divert water rights.
Diversion for irrigation prior to 1896 when the River Law was
enforced was considered a traditional water right， already approved at the
time of enforcement. In this way， the water rights of irrigation groups
with a long history have been legally recognized.
In view of the definition under the River Law that river water is a
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Chapter 8
public asset， irrigation groups are prohibited to directly sell their water
rights to cities. In reality， however， there have been a few cases of water
rights being sold.
Today， projects have been startedto reduce distribution loss by works
-(lining， installation of check gates on open channels or pipe lines to replace
former open channel systems). The cities in turn pay the costs of modify-
ing such irrigation facilities. Part of the irrigation water which has
become unnecessary， due to decreased irrigation areas resulting from
urbanization， are transferred to cities.
farm
tertiary
farm
4Ilk-↓
farm drain
farm road
Figure 7 Standard paddy field layout after ∞nsolidation.
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M iscellaneous
8・11Standard plot size and its development for paddy field land
consolidation projects
From around 1965 to recent years， a plot of 3，000 m2 (30 ares) has been
considered a standard size for paddy land consolidation projects. This
basic size is 100 meters long and 30 meters wide， with a farm ditch， farm
drain and farm road along the shorter side. These land consolidation
projects with a plot of 30 ares as a srandard size have rapidly spread， and
today paddy fields under such projects account for 45% of the total paddy
fields. In comparison with the 1 hectare of paddy-Iand-holding of the
average farmer in Japan， plots of 30 ares made it easy to consolidate
dispersed plots and then to return it to those farmers participating in land
consolidation projects. In alloting land， adjustment of participants' inter-
ests was relatively easy; plots of 30 ares were such that farmers could to
some extent efficiently utilize their tractors and other farming machinery.
In recent years， however， to further effectively use of farming machin圃
ery and improve capital and labor productivity， land consolidation projects
have started to make plots of at least 50 ares each.
8・12 Sophistication of irrigation and drainage facilities
Today， to save labor for operation and maintenance and to realize a
precise water management， advanced and sophisticated equipment is
installed or delivery canal systems are remote-controlled or automatic-
controlled.
8・13 Drainage projects
For removing the surface water f100ded into paddy fields， drainage
pumps and/or canals have been constr-ucted with such capacity to drain a
rainfall of 1QO mm/day in three days. Today， such capacity is considered
insufficient， especially in paddy fields where paddy， non-paddy grains and
vegetables are grown on a rotatioan basis. Ponded water is harmful for the
- 67ー
Cha;争Ite:γ8
latter， and rapid drainage is essential. Even with paddy fields， subsur-
face drainage is required in many cases， and some paddy fields are
provided with tile drains.
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